US Pat. No. 9,451,262

METHOD AND APPARATUS FOR INTRA-PREDICTION ENCODING/DECODING

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a macroblock which is divided into a plurality of blocks, the apparatus comprising:
a prediction mode selector configured to select an intra prediction mode related to a prediction direction with respect to
each of the blocks in the macroblock by calculating a similarity between previously encoded pixels adjacent to a block to
be encoded in the macroblock and selecting an intra prediction mode of the block to be encoded based on the similarity between
the previously encoded pixels, wherein the prediction mode selector is configured to

select, when the similarity between the previously encoded pixels is equal to or higher than a threshold, a predetermined
default intra prediction mode as the intra prediction mode of the block to be encoded, and

select, when the similarity between the previously encoded pixels is lower than the threshold, the intra prediction mode of
the block to be encoded from among a plurality of intra prediction modes;

an intra prediction encoder configured to encode a residual block generated by intra-predicting each of the blocks according
to the selected intra prediction mode corresponding thereto to generate information on transform coefficients; and

a bitstream generator configured to
encode a mode identifier for indicating the intra prediction mode of the block to be encoded among the plurality of intra
prediction modes when the intra prediction mode of the block to be encoded is selected from among the plurality of intra prediction
modes, wherein the mode identifier of the block to be encoded is not encoded when the predetermined default intra prediction
mode is selected as the intra prediction mode of the block to be encoded, and

generate a bitstream including a mode bit field and a coefficient bit field, wherein the mode bit field include encoded mode
identifiers for one or more blocks in the macroblock and the coefficient bit field include the information on transform coefficients
of all blocks in the macroblock.

US Pat. No. 9,560,379

INTER-PREDICTION METHOD AND VIDEO ENCODING/DECODING METHOD USING THE INTER-PREDICTION METHOD

SK TELECOM CO., LTD., Se...

1. A video encoding method using inter-prediction, comprising:
encoding a first picture, wherein the first picture serves as a random access picture and is encoded without referring to
a reference picture which has already encoded and then decoded;

inter-prediction encoding blocks included in a second picture, which is encoded after the first picture and displayed before
the first picture, by using a plurality of reference pictures;

generating reference picture information representing the reference pictures used for encoding the second picture among reference
pictures including one or more reference pictures encoded before the first picture; and

transmitting the encoded first picture and the encoded second pictures and the reference picture information,
wherein the one or more reference pictures encoded before the first picture are adaptively deleted from a memory based on
whether or not the one or more reference pictures encoded before the first picture are used for encoding the second picture,
and

when the one or more reference pictures encoded before the first picture are used as the reference pictures for encoding the
second picture, the one or more reference pictures encoded before the first picture are deleted from the memory after encoding
at least the second picture, and

wherein the memory includes a reference picture list 0 into which past reference pictures displayed before the second picture to be encoded are inserted and a reference picture
list 1 into which future reference pictures displayed after the second picture to be encoded are inserted, and

the reference picture list 0 is allowed to include, in addition to the past reference pictures, one or more future reference pictures which are inserted
into the reference picture list 1.

US Pat. No. 9,473,777

VIDEO ENCODING DEVICE AND ENCODING METHOD THEREOF, VIDEO DECODING DEVICE AND DECODING METHOD THEREOF, AND DIRECTIONAL INTRA-PREDICTION METHOD TO BE USED THERETO

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a current block, the apparatus comprising:
a main mode search circuit configured to select a main mode of the current block from among a plurality of directional intra-prediction
modes;

a sub mode search circuit configured to select a sub mode corresponding to the main mode, wherein the sub mode has a direction
defined by rotation of a direction of the main mode by a predetermined angular offset;

a predicted block generator configured to generate a predicted block of the current block from reference pixels in at least
one neighboring block adjacent to the current block based on the main mode and the sub mode,

wherein the predicted block generator is configured to shift the reference pixels by one pixel horizontally or vertically
and generate the predicted block by using the shifted reference pixels in the direction of the main mode and

wherein a direction of the shifting and the direction of the main mode correspond to the direction of the sub mode;
a differentiator configured to calculate a differential between the current block and the predicted block; and
an encoder configured to encode the differential and information on the main mode and the sub mode.

US Pat. No. 9,083,723

METHOD FOR PROVIDING EARLY-MEDIA SERVICE BASED ON SESSION INITIATION PROTOCOL

SK TELECOM CO., LTD., Se...

1. A method of a session initiation protocol (SIP) based call connection by a terminating terminal, the method comprising:
receiving an invite message containing a first session description protocol (SDP) information on an originating terminal via
an application server;

transmitting a 180 ringing message containing a second SDP information on the terminating terminal to the application server,
prior to transmitting a call response message, wherein the terminating terminal transmits the 180 ringing message after the
application server acquires media information for early media and provides the early media to the originating terminal;

transmitting the call response message responsive to the invite message to the application server; and
establishing a call with the originating terminal,
wherein the second SDP information is provided to the originating terminal by the application server before the terminating
terminal transmits the call response message.

US Pat. No. 9,491,694

OPERATION METHOD OF USER EQUIPMENT IN MULTI-CARRIER SYSTEM

SK TELECOM CO., LTD., Se...

1. A User Equipment (UE) accessing a wireless communication system operating a Multi-Carrier (MC), the UE comprising:
an access history identification unit configured to, when the UE accesses the wireless communication system in a first frequency
band on which the UE is camped, identify whether the UE stores an access fail history of the first frequency band by referring
to an access fail counter for the first frequency band;

a search unit configured to, when the UE stores the access fail history of the first frequency band,
receive a parameter indicating an accessibility to the wireless communication system in a second frequency band, which is
different from the first frequency band, and

search for the second frequency band based on the received parameter; and
an access control unit configured to, when the wireless communication system is found in the second frequency band based on
a result of the search, access the wireless communication system through the second frequency band,

wherein the access history identification unit does not increase a value of the access fail counter for the first frequency
band when the RRC connection reject message, which does not include wait time information is received through the first frequency
band.

US Pat. No. 9,060,284

METHOD AND DEVICE FOR ESTIMATING AP POSITION USING A MAP OF A WIRELESS LAN RADIO ENVIRONMENT

SK TELECOM CO., LTD., Se...

1. An apparatus for estimating an AP position by using a weighted average of signal strengths, comprising:
a filtering unit for generating a filtering radiowave map with data selected exclusively for having a common MAC address from
collected wireless LAN radiowave environment maps;

a grid cell division unit for generating a grid radiowave map with arbitrary grid cells from dividing the filtering radiowave
map;

a representative coordinate mapping unit for calculating a centroid of each of the grid cells constituting the grid radiowave
map, and mapping said each centroid as a representative coordinate to said each grid cell;

a representative signal strength mapping unit for calculating representative signal strengths based on data existing in said
each grid cell, and mapping each representative signal strength to said each grid cell;

a weight value sorting unit for sorting out a weight value corresponding to a range covering a received signal strength of
the representative signal strength; and

a position estimation unit for estimating positional information of access points (APs) having a common MAC address based
on one or more of the representative coordinate, the representative signal strength, and the weight value.

US Pat. No. 9,451,270

VIDEO ENCODING/DECODING APPARATUS AND METHOD USING BATCH MODE TOGETHER WITH SKIP MODE

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoder configured to reconstruct a syntax corresponding to at least one of a first block, a second block and a third block,
wherein

the first block is generated by dividing a frame for decoding,
the second block corresponds to a unit of a prediction and is generated by dividing the first block, and
the third block corresponds to a unit of transformation and is generated by dividing the first block in a tree structure;
and

a predictor configured to reconstruct a prediction block corresponding to at least one of the first block, the second block
and the third block,

wherein a prediction pixel in the prediction block is generated by averaging a horizontal prediction value of the prediction
pixel and a vertical prediction value of the prediction pixel,

wherein the horizontal prediction value is calculated by using a pixel adjacent to the left side of the prediction block and
an upper-right pixel outside the prediction block, and the vertical prediction value is calculated by using a pixel adjacent
to the upper side of the prediction block and a lower-left pixel outside the prediction block, and

wherein the upper-right pixel outside the prediction block is commonly used to calculate the horizontal prediction value of
each prediction pixel in the prediction block, and the lower-left pixel outside the prediction block is commonly used to calculate
the vertical prediction value of each prediction pixel in the prediction block.

US Pat. No. 9,424,251

METHOD FOR EXTRACTING SEMANTIC DISTANCE FROM MATHEMATICAL SENTENCES AND CLASSIFYING MATHEMATICAL SENTENCES BY SEMANTIC DISTANCE, DEVICE THEREFOR, AND COMPUTER READABLE RECORDING MEDIUM

SK TELECOM CO., LTD., Se...

1. An apparatus for extracting a semantic distance, the apparatus comprising:
a user query input unit configured to receive a user query;
a query parsing unit configured to extract at least one keyword included in the received user query;
an index information unit configured to index one or more of natural language tokens and mathematical equation tokens, wherein
the natural language tokens and the mathematical equation tokens each include semantic information;

a semantic distance extraction unit configured to
extract a semantic distance, between the at least one extracted keyword and the one or more indexed semantic information,
and

acquire a similarity of the received user query and the semantic information based on the extracted semantic distance; and
a semantic parsing unit (120) individually divide the natural word and the mathematical equation from the composite sentence, by perform a process of
tokenizing the natural language tokens to generate the natural word and classify the composite sentence, wherein the process
of tokenizing includes (i) a process of filtering a stop word based on the natural language token to generate a stop word
filtering data, (ii) a process of redundancy removal filtering on the stop word filtering data to generate a redundancy removal
filtering data, and (iii) a process of matching a predefined meaningful action to the redundancy removal filtering data.

US Pat. No. 9,491,467

METHOD AND APPARATUS FOR IMAGE ENCODING/DECODING

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using an intra prediction, the apparatus comprising:
a decoder, implemented by one or more processors and, configured to obtain mode information of a current block and residual
sub-blocks corresponding to a plurality of sub-blocks included in the current block, from a bitstream;

an intra predictor, implemented by one or more processors and, configured to
select an intra prediction mode of the current block from among a plurality of intra prediction modes, based on the obtained
mode information,

identify the plurality of sub-blocks of the current block, and
sequentially predict the plurality of sub-blocks by using neighboring pixels adjacent to each of the plurality of sub-blocks,
wherein each of the plurality of sub-blocks is predicted by using the same intra prediction mode of the current block selected
based on the obtained mode information;

an inverse quantization and transform unit, implemented by one or more processors and, configured to inversely quantize and
then inversely transform each of the residual subblocks; and

an adder, implemented by one or more processors and, configured to sequentially reconstruct the plurality of sub-blocks by
adding each of the predicted sub-blocks to an inversely quantized and inversely transformed residual sub-block corresponding
thereto,

wherein one or more pixels of a pre-reconstructed sub-block within the current block are used as part of the neighboring pixels
for predicting at least one non-reconstructed sub-blocks adjacent to the pre-reconstructed sub-block.

US Pat. No. 9,445,098

APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING PREDICTABILITY OF INTRA-PREDICTION MODE

SK TELECOM CO., LTD., Se...

1. A method for decoding a video comprising:
extracting mode information for predicting a current block from encoded data;
deriving a set of candidate intra-prediction modes including at least three candidate intra-prediction modes, depending on
the current block;

determining a candidate intra-prediction mode selected from the derived set of candidate intra-prediction modes as the intra-prediction
mode of the current block without comparing mode numbers of candidate intra-prediction modes included in the derived set each
other, when the mode information indicates a first encoding mode;

determining the intra-prediction mode of the current block by using a prediction mode identification information, when the
mode information indicates a second encoding mode and includes the prediction mode identification information;

generating a prediction block by predicting the current block based on the determined intra-prediction mode of the current
block, and decoding the encoded data to produce a residual block; and

reconstructing the current block by adding the residual block to the prediction block.

US Pat. No. 9,420,293

IMAGE CODING/DECODING DEVICE USING CODING BLOCK IN WHICH INTRA BLOCK AND INTER BLOCK ARE MIXED, AND METHOD THEREOF

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a coding unit, the apparatus comprising:
a predictor configured
to divide the coding unit into a plurality of subblocks,
to determine respective prediction modes for respective subblocks of the plurality of subblocks of the coding unit from among
a plurality of intra prediction modes and plurality of inter prediction modes,

to determine, when the coding unit includes a plurality of intra prediction subblocks of the plurality of subblocks, an encoding
order among the intra prediction subblocks within the coding unit by comparing numbers of reconstructed neighboring blocks
that are available to respective ones of the intra prediction subblocks for use in intra prediction, wherein the intra prediction
subblocks are subblocks to be predicted by respective intra predictions, and

to perform each intra prediction for each of the intra prediction subblocks according to the determined encoding order to
thereby generate each predicted block of said each of the intra prediction subblocks;

a subtractor configured to generate each residual block of said each of the intra prediction subblocks, by subtracting said
each predicted block of said each of the intra prediction subblocks from said each of the intra prediction subblocks;

a transformer/quantizer configured to generate each quantized transform coefficient by transforming and quantizing said each
residual block of said each of the intra prediction subblocks; and

an encoder configured to generate encoded video data by encoding said each quantized transform coefficient into a bitstream.

US Pat. No. 9,374,584

APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING PREDICTABILITY OF INTRA-PREDICTION MODE

SK TELECOM CO., LTD., Se...

1. An apparatus for decoding a video, the apparatus comprising:
a mode information extractor configured to extract mode information on an intra-prediction mode of a current block from encoded
data;

a prediction mode determiner configured to
derive a set of candidate intra-prediction modes including at least three candidate intra-prediction modes, depending on the
current block, wherein the derived set of candidate intra-prediction modes includes an intra-prediction mode of at least one
neighboring block adjacent to the current block when the intra-prediction mode of the at least one neighboring block is available,
and

determine a candidate intra-prediction mode selected from the derived set of candidate intra-prediction modes as the intra-prediction
mode of the current block without comparing mode numbers of candidate intra-prediction modes included in the derived set each
other, when the mode information indicates a first encoding mode;

a prediction mode extractor configured to determine the intra-prediction mode of the current block by using a prediction mode
identification information, when the mode information indicates a second encoding mode and includes the prediction mode identification
information; and

a decoder configured to decode the encoded data to produce a residual block, and reconstruct the current block by adding the
produced residual block to a prediction block predicted based on the intra-prediction mode of the current block determined
by either the prediction mode determiner or the prediction mode extractor.

US Pat. No. 9,491,681

APPARATUS AND METHOD FOR SUPPORTING DATA TRANSMISSION SERVICE OVER MULTIPLE NETWORKS

SK TELECOM CO., LTD., Se...

1. A transmitting device, comprising:
a communication unit configured to
transmit data through two or more networks including a first network and a second network,
receive a message indicating a data roundabout transmission request state of a receiving device with respect to the first
network from the receiving device, and

a transmission controller configured to
control the communication unit to
transmit the data to the receiving device through the first network, and
transmit the data, which is to be transmitted to the receiving device through the first network, to the receiving device in
a roundabout way through the second network in response to the message, and

end transmitting the data in the roundabout way through the second network to transmit the data through the first network
when the state of the receiving device is determined to escape from the roundabout transmission request state with respect
to the first network,

wherein the transmission controller is configured to identify, from the message, whether the receiving device is in the data
roundabout transmission request state, based on at least one selected from the group consisting of an available bandwidth,
a connection error generation state, a predetermined delay value of receiving the data with respect to the first network,

the transmission controller is configured to identify that the receiving device is in the data roundabout transmission request
state when the data transmitted to the receiving device through the first network indicate a particular data service type,
wherein the particular data service type includes at least one selected from the group consisting of: a service type of traffic
capacity larger than a predetermined threshold; bidirectional communication traffic,traffic requiring security; a predetermined
traffic for information collection; and a predetermined control signal.

US Pat. No. 9,432,853

POSITIONING DEVICE OF MOBILE COMMUNICATION TERMINAL, METHOD FOR CONSTRUCTING WIRELESS LAN INFORMATION OF DEVICE, POSITIONING SERVER OF MOBILE COMMUNICATION TERMINAL, AND METHOD FOR DRIVING SERVER

SK TELECOM CO., LTD., Se...

1. A system, comprising:
a node information-based server configured to store wireless environment information of a node in charge of communications
of a mobile communication terminal, wherein the wireless environment information comprises latitude and longitude coordinates
of the node;

a wireless LAN server configured to store wireless LAN information of a plurality of access points, wherein the wireless LAN
information comprises latitude and longitude coordinates of the plurality of access points; and

a positioning server configured to:
request positioning information of the mobile communication terminal and receive the positioning information of the mobile
communication terminal from the mobile communication terminal, wherein the positioning information comprises information of
an access point among the plurality of access points, said access point performing wireless LAN communication with the mobile
communication terminal,

request the wireless environment information of the node and receive the wireless environment information of the node from
the node information-based server,

request the wireless LAN information of the access point and receive the wireless LAN information of the access point from
the wireless LAN server,

calculate a distance between the access point and the node, based on the wireless LAN information of the access point, and
the wireless environment information of the node,

determine whether the access point has moved by comparing the calculated distance with a predetermined distance, and
request the wireless LAN server to delete the wireless LAN information of the access point from the wireless LAN server when
the calculated distance is greater than or equal to the predetermined distance,

wherein the positioning server is configured to calculate the distance between the access point and the node by comparing
the latitude and longitude coordinates of the node with the latitude and longitude coordinates of the access point.

US Pat. No. 9,390,053

CACHE DEVICE, CACHE CONTROL DEVICE, AND METHODS FOR DETECTING HANDOVER

SK TELECOM CO., LTD., Se...

1. A cache device comprising:
a storage unit comprising a hardware memory configured to store at least one content and terminal access information received
from at least one other cache device; and

a controller comprising one or more programmed processors configured
to monitor messages transmitted from at least one user terminal for a content retransmission request message, wherein the
content retransmission request message is a request for previously cached content,

to extract terminal address information of the user terminal from the content retransmission request message when the content
retransmission request message is detected, and

if the extracted terminal address information is included in the stored terminal access information, to notify a handover
of the user terminal to the at least one other cache device which sends the stored terminal access information,

wherein the controller is further configured
to extract content requested by the user terminal from the storage unit, and
to provide the extracted content to the user terminal, and
wherein, after notifying the handover of the user terminal to the at least one other cache device, the controller is further
configured

to receive, from the at least one other cache device, content information including content identification information and
information about a content interruption point to the user terminal by the at least one other cache device, and

to provide, to the user terminal, data for a portion after the content interruption point among the content corresponding
to the content identification information.

US Pat. No. 9,464,937

METHOD AND DEVICE FOR DIFFERENTIAL OPTICAL PHASE MODULATION IN QUANTUM KEY DISTRIBUTION SYSTEM

SK TELECOM CO., LTD., Se...

1. A transmitting apparatus in a quantum key distribution system, the apparatus comprising:
an optical interferometer configured to
receive a single-photon pulse inputted from a light source and
provide the single-photon pulse with two optical paths having a predetermined path difference between a first optical path
and a second optical path, the two optical paths including the first optical path and the second optical path and being used
for the single-photon pulse to pass through the optical interferometer, wherein the single-photon pulse, after passing through
the optical interferometer, has a probability distribution divided into two separate regions in a time domain; and

an optical phase modulator configured to perform a temporal differential phase modulation of the single-photon pulse which
has passed through the optical interferometer, by imparting a phase-shift oppositely to the single-photon pulse for the two
separate regions.

US Pat. No. 9,462,279

IMAGE ENCODING/DECODING METHOD AND DEVICE

SK TELECOM CO., LTD., Se...

1. A video decoding method, comprising:
determining a current block to be decoded, by decoding block size information from a bitstream;
decoding a skip information of the current block from the bitstream, the skip information indicating whether the current block
is a skip block;

when the skip information indicates that the current block is the skip block,
decoding a skip motion information of the current block from the bitstream, and
reconstructing the current block directly from a predicted block predicted based on the skip motion information, without reconstructing
a residual signal information from the bitstream; and

when the skip information indicates that the current block is not the skip block,
decoding an intra or inter prediction information of the current block and a residual signal information from the bitstream,
and

reconstructing the current block based on the prediction information and the residual signal information,
wherein the determination of the current block to be decoded comprises:
decoding a bitstream to reconstruct a first information on a minimum block size and a second information on a difference between
a maximum block size and the minimum block size,

determining the maximum block size based on the first and second information,
reconstructing a partition flag indicating whether each node, starting from a node of an uppermost layer having the maximum
block size in a tree structure, is partitioned into four nodes of a lower layer, and

identifying, as the current block to be decoded, a block corresponding to a node which is not further partitioned.

US Pat. No. 9,420,304

APPARATUS AND METHOD FOR MOTION VECTOR ENCODING/DECODING, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using an inter-prediction, the apparatus comprising:
a decoder configured to reconstruct a flag and quantized transform coefficients by decoding a bitstream, the flag indicating
one among a plurality of modes for determining the motion vector of the current block;

a predictor configured to determine a motion vector of a current block to be decoded in a current picture, and predict pixels
in current block using the motion vector of the current block;

an inverse quantizer and inverse transformer configured to inversely quantize and then inversely transform the quantized transform
coefficients to thereby reconstruct residual signals; and

an adder configured to add the predicted pixels to the reconstructed residual signals which correspond to the predicted pixels,
wherein, when the flag indicates a first mode among the plurality of modes, the predictor is configured to
derive a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block,
select a candidate motion vector from the set of candidate motion vectors,
set a predicted motion vector of the current block to the selected candidate motion vector, and
determine the motion vector of the current block by adding the predicted motion vector of the current block to a differential
vector decoded from the bitstream.

US Pat. No. 9,369,714

METHOD FOR ENCODING/DECODING MOTION VECTOR AND APPARATUS THEREOF

SK TELECOM CO., LTD., Se...

1. A method for decoding a current motion vector of a current block, which is located in a current picture, at an apparatus
for decoding an encoded video, the method comprising:
extracting, from a bitstream, mode information for use in selecting a motion vector prediction mode among a plurality of motion
vector prediction modes, wherein the plurality of motion vector prediction modes are different from each other and indicate
different ways to determine the current motion vector of the current block; and

when the mode information indicates a first motion vector prediction mode among the plurality of motion vector prediction
modes, performing a process comprising:

decoding the bitstream to produce a differential vector of the current block;
deriving a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block,
wherein the set of candidate motion vectors is used for determining a prediction motion vector of the current block, not determining
the current motion vector itself of the current block, to be added to the produced differential vector,

wherein the plurality of neighboring blocks include at least one block spatially adjacent to the current block in the current
picture and at least one block in a reference picture other than the current picture, wherein a position of said at least
one block in the reference picture is derived based on a position of the current block in the current picture;

selecting a candidate motion vector from among the set of the candidate motion vectors;
determining a prediction motion vector of the current block as the selected candidate motion vector, wherein the selected
candidate motion vector has been derived from said at least one block spatially adjacent block or said at least one block
in a reference picture; and

reconstructing the current motion vector of the current block by adding the produced differential vector to the prediction
motion vector of the current block,

wherein the at least one block spatially adjacent to the current block includes one or more of blocks located at left, upper,
upper right and upper left sides of the current block.

US Pat. No. 9,198,128

METHOD AND APPARATUS FOR DISCONTINUOUS TRANSMISSION/RECEPTION OPERATION FOR REDUCING POWER CONSUMPTION IN CELLULAR SYSTEM

ELECTRONICS AND TELECOMMU...

1. A method for discontinuously transmitting and/or receiving packet data to reduce power consumption of a terminal in a cellular
system, comprising:
establishing discontinuous reception and/or transmission (DRX/DTX) parameters including DRX/DTX cycle information for terminals
in an active state in which the terminals are capable of transmitting or receiving data; and

performing DRX/DTX based on the DRX/DTX parameters for the terminals operating the DRX/DTX in the active state,
wherein the terminals operate in the active state or an idle state.

US Pat. No. 9,503,721

METHOD AND APPARATUS FOR PREDICTIVE ENCODING/DECODING OF MOTION VECTOR

SK TELECOM CO., LTD., Se...

1. A video decoding method performed by a video decoding apparatus for predicting a current block to be decoded, the method
comprising:
extracting an index for use in identifying a predicted motion vector of the current block and a differential motion vector
from a bitstream;

determining one or more representative blocks using neighboring blocks of the current block, in consideration of priorities
of block positions;

determining the predicted motion vector of the current block to be a motion vector identified by the extracted index; and
generating a predicted block of the current block by reconstructing a motion vector of the current block based on the determined
predicted motion vector and the extracted differential motion vector,

wherein the determining of the one or more representative blocks comprises considering a difference between a first picture
order count (POC) corresponding to a first reference picture of a neighboring block and a second picture order count (POC)
corresponding to a second reference picture of the current block when a first inter prediction direction corresponding to
the neighboring block and a second inter prediction direction corresponding to the current block are identical.

US Pat. No. 9,258,737

DEVICE AND METHOD FOR SIMULTANEOUSLY TRANSMITTING DATA IN MULTI-NETWORK

SK TELECOM CO., LTD., Se...

1. A receiving device, comprising:
a communication unit configured to receive a plurality of partial data divided from data to be transmitted through two or
more connection networks;

an information confirming unit configured to confirm
(i) transmission order information indicating a transmission order assigned to each of the plurality of partial data to be
transmitted through the two or more connection networks, and

(ii) network transmission order information indicating a transmission order assigned to specific partial data among the plurality
of partial data to be transmitted through a specific connection network designated among the two or more connection networks;
and

a control unit configured to determine whether non-received partial data are lost based on at least one of the transmission
order information and the network transmission order information.

US Pat. No. 9,750,073

DEVICE AND METHOD FOR CONCURRENT CALL AVOIDANCE

SK TELECOM CO., LTD., Se...

1. A terminal device, comprising:
a state determining unit, comprising one or more processors and/or application-specific integrated circuits (ASICs), configured
to

determine period information of a transfer period, the period information designated to a specific application, wherein the
terminal device designates the transfer period to transfer one or more periodic messages, wherein the periodic messages are
to be repeatedly transferred to a server during the transfer period, and indicates whether to keep maintaining a session of
a data call related to the specific application,

set a detection period to detect a connection of a voice call, wherein the detection period is set, based on the determined
period information of the transfer period, to be an interval having a specific time predetermined prior to and shorter than
the transfer period, wherein the terminal device designates the periodic messages to notify the server of whether to keep
maintaining the session of the data call established between the terminal device and the server, and

determine, during the detection period, whether a current connection state is in a voice call connected state or whether the
current connection state is in a state of a data call connected state in order to thereby transfer one or more periodic messages
if the current connection state is not in the voice call connected state, and skip transferring any periodic messages indicating
whether to keep maintaining the session of the data call if the current connection state is in the voice call connected state;
and

an application interworking unit, comprising one or more processors and/or application-specific integrated circuits (ASICs),
configured to

determine, during the transfer period, whether the current connection state is the voice call connected state, and transfer
the periodic messages through the data call when the state determining unit determines that the current connection state is
in a state of the voice call connected state, and

skip transferring, at a further transfer period other than the transfer period corresponding to the period information, any
periodic messages indicating whether to keep maintaining the session of the data call related to the specific application,
when the state determining unit determines that the current connection state is in a state of the voice call connected state
during the session of the data call, in order to minimize simultaneously performing multiple radio access bearer connection.

US Pat. No. 9,432,663

METHOD AND APPARATUS FOR CODING/DECODING IMAGE

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a video, the apparatus comprising:
a bitstream decoder configured to extract information on a size of a transform unit and generate a quantized frequency transform
block from a bitstream;

an inverse quantization unit configured to reconstruct a frequency transform block by inversely quantizing the quantized frequency
transform block;

an inverse transformer configured to reconstruct a residual block by inversely transforming the frequency transform block,
the inverse transformer selecting an inverse transform scheme among a plurality of inverse transform schemes in consideration
of the size of the transform unit;

a predictor configured to generate a predicted block in a prediction mode selected among an intra prediction mode and an inter
prediction mode; and

an adder configured to reconstruct a current block by adding a first pixel corresponding to the residual block and a second
pixel corresponding to the predicted block,

wherein the inverse transformer considers a first transform scheme only when the size of the transform unit corresponds to
a transform unit size of 4×4 among a plurality of available transform unit sizes,

wherein the transform unit is divided from a coding unit in a quad tree, and the bitstream decoder decodes a split transform
flag, as one of the information on the size of the transform unit, for at least one depth of the quad tree,

wherein the first transform scheme corresponds to a transform scheme in which each of four output values {X?(0), X?(1), X?(2), X?(3)} is generated by using at least two of four input values {X(0), X(1), X(2), X(3)} multiplied by coefficients corresponding to each of the input values,

wherein the transform scheme in which each of four output values {X?(0), X?(1), X?(2), X?(3)} is generated corresponds to a transform in which,

a first group of the coefficients used for generating the first output value X?(0) includes a coefficient for the X(0), a coefficient for the X(1) and a coefficient for the X(2), all having positive signs,

a second group of the coefficients used for generating the second output value X?(1) includes a coefficient for the X(0) and a coefficient for the X(1), both having positive signs,

a third group of the coefficients used for generating the third output value X?(2) includes a coefficient for the X(1) and a coefficient for the X(2), both having negative signs, and

a fourth group of the coefficients used for generating the fourth output value X?(3) included a coefficient for the X(1), having a negative sign, and a coefficient for the X(2), having a positive sign.

US Pat. No. 9,372,828

METHOD AND DEVICE FOR INPUTTING EQUATION

SK TELECOM CO., LTD., Se...

1. An equation input apparatus, comprising:
a learning context recognizer configured to extract learning context information based on a learner account of a learner,
wherein the learner account is provided with learning content information;

a target equation group extractor configured to generate a target equation group including target mathematical symbols based
on the extracted learning context information;

a predicted equation provider configured to
predict a predicted mathematical symbol list relating to information inputted or selected, by a learner command of the learner,
from the target equation group, and

provide an equation selected, by the learner, from the predicted mathematical symbol list; and
a typo indicator configured to check whether equation information or text information inputted or selected by the learner
command is a typo or not based on prestored decision information and, if the typo is confirmed, to automatically indicate
a typo state of the equation information or text information,

wherein the extracted learning context information includes at least one of learning field information, learning subject information,
learner nationality information of the learner, learner grade information of the learner, equation type information included
in a relevant learning content, and cumulative equation information regarding equations selected by the learner, and

wherein the prestored decision information includes at least one of equation information included in the learning content
information, text information included in learning subject information of the learning context information, and equation information
or text information included in entire curriculum information which corresponds to the learner's level of the learning context
information.

US Pat. No. 9,426,491

IMAGE ENCODING/DECODING METHOD AND APPARATUS USING BLOCK TRANSFORMATION

SK TELECOM CO., LTD., Se...

1. A method of encoding an intra block in the unit of sub-blocks, the method comprising:
selecting an intra prediction mode of the intra block from among a plurality of intra prediction modes;
dividing the intra block into a plurality of sub-blocks;
encoding information on the selected intra prediction mode of the intra block into a bitstream; and
encoding the plurality of sub-blocks into the bitstream based on sequentially predicting the plurality of sub-blocks in a
predefined order by using neighboring pixels adjacent to each of the plurality of sub-blocks,

wherein each of the plurality of sub-blocks is predicted by using the same intra prediction mode as the selected intra prediction
mode of the intra block,

wherein the number of pixels of each sub-block is the square of a natural number,
wherein the encoding of the plurality of sub-blocks comprises:
predicting a first sub-block of the sub-blocks based on the same intra prediction mode as the selected intra prediction mode
of the intra block to generate a predicted sub-block;

generating a residual sub-block by subtracting the predicted sub-block from the first sub-block;
generating a reconstructed sub-block by using the residual sub-block and the predicted sub-block;
identifying one or more pixels in the reconstructed sub-block for predicting a second sub-block which is subsequent to the
first sub-block in the predefined order, the one or more pixels in the reconstructed sub-block being located adjacent to the
second sub-block; and

predicting the second sub-block based on the same intra prediction mode as the selected intra prediction mode of the intra
block, and based on the one or more pixels in the reconstructed sub-block, instead of original pixels in the first sub-block,

wherein the plurality of sub-blocks have a size L×M, respectively,
where L is a horizontal length, M is a vertical length, L is unequal to M, and L and M are natural numbers,
wherein the values of L and M are determined in accordance with a prediction direction of the selected intra prediction mode,
wherein the value of L is greater than the value of M when the prediction direction is vertical or the value of L is smaller
than the value of M when the prediction direction is horizontal.

US Pat. No. 9,405,685

METHOD OF PROVIDING CONTENT DURING HAND-OVER AND APPARATUS THEREFOR

SK TELECOM CO., LTD., Se...

1. A mobile CDN controller, comprising:
a communication interface for communicating with a plurality of local caching devices distributed in a mobile network and
a packet core of the mobile network; and

a content transmission controller for receiving, from a specific local caching device from among the plurality of local caching
devices, a signal representing a hand-over of a mobile node to which the specific local caching device currently transmits
content data, determining a selected one of local caching devices capable of transmitting the content data to the mobile node,
and controlling the content data stored in one of the specific local caching device, the selected local caching device and
a origin server to be transmitted to the mobile node according to whether the selected local caching device stores the content
data.

US Pat. No. 9,402,084

METHOD AND APPARATUS FOR VIDEO ENCODING/DECODING USING IMPROVED MERGE

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a bitstream decoder configured to extract a merge flag and a merge index from a bitstream;
an inter predictor responsive to the merge flag indicating a merge mode, and configured to
check for whether predetermined candidate adding conditions are satisfied;
add into a merge candidate set including the merge candidates corresponding to neighboring blocks of a current block, a combined
bi-predictive motion parameter, the combined bi-predictive motion parameter generated by combining a list 0 motion parameter of a first available candidate block and a list 1 motion parameter of a second available candidate block, when the predetermined candidate adding conditions are satisfied,
and

generate a predicted block of the current block by using a motion parameter corresponding to a merge candidate selected from
the merge candidate set, the merge candidate selected by the extracted merge index,

wherein the merge candidate set is generated based on a maximum number of the merge candidates, the maximum number of the
merge candidates decided using information on the number of the merge candidates included in the bitstream.

US Pat. No. 9,467,360

SYSTEM, DEVICE AND METHOD FOR MANAGING NETWORK TRAFFIC BY USING MONITORING AND FILTERING POLICIES

SK TELECOM CO., LTD., Se...

12. A method for controlling data traffic by using a monitoring policy and a filtering policy, the method performed by a traffic
control device implemented by one or more processors and/or application-specific integrated circuits (ASICs) to execute the
method comprising:
receiving the monitoring policy from a network traffic managing device;
collecting packets generated in one or more applications of a user terminal device, according to port numbers in the user
terminal device;

detecting the packets conforming to the monitoring policy according to the one or more applications or one or more destination
addresses through monitoring the received packets at a kernel area of the user terminal device, wherein the monitoring policy
includes at least one selected from the group consisting of an application list, protocol information, the port numbers, a
packet creation period and the destination addresses, and

the monitoring policy is created to detect packets of applications installed in the user terminal device, the packets of the
applications being transmitted to a service providing device, and;

creating traffic statistical information through an analysis of the detected packets;
transmitting the traffic statistical information to the network traffic managing device, the traffic statistical information
used to create a filtering policy by the network traffic managing device;

receiving the filtering policy from the network traffic managing device, wherein the filtering policy includes at least one
selected from the group consisting of a blocked application list and a blocked destination address list, and the filtering
policy is created to block data traffic of all or a part of packets causing communication network overloads based on the transmitted
traffic statistical information; and

filtering the packets of the one or more applications or packets having one or more blocked destination addresses by blocking
data traffic of all or a part of packets causing communication network overloads based on the filtering policy, at the kernel
area of the user terminal device.

US Pat. No. 9,113,166

APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING CONSIDERING IMPULSE SIGNAL

SK TELECOM CO., LTD., Se...

1. A method for video encoding, the method comprising:
generating a predicted block by predicting a current block;
generating an M×N residual block by subtracting the predicted block from the current block; when the M×N residual block includes
no impulsive components having values larger than the predetermined value, setting all residual signals of the M×N residual
block to zero; and

when one or more of frequency coefficients generated through transformation and quantization of the M×N residual block are
not zero, and

when the M×N residual block contains one or more impulsive components having values larger than a predetermined value, performing
sub-steps of:

selecting an A×B residual block containing the impulsive components and then transforming the A×B residual block into frequency
coefficients, wherein wherein the A×B residual block is selected such that the A×B residual block is smaller in size than
the entire M×N residual block; and the number of pixels in the A×B residual block is more than a predetermined number,

encoding the frequency coefficients of the A×B residual block into a bitstream, and
encoding information on a position and a size of the A×B residual block into the bitstream,
wherein residual signals in the M×N residual block, which are excluded from the A×B residual block, are not encoded into the
bitstream.

US Pat. No. 9,054,991

MANAGING METHOD AND APPARATUS FOR SERVICING CONTENTS PROVIDED BY CONTENT PROVIDER

SK TELECOM CO., LTD., Se...

1. A managing method for contents providing services, the method comprising the steps of:
(A-1) providing a website server account of a Contents Provider (CP) based on information of the CP provided via a contents
providing apparatus;

(A-2) registering a contents connection point which is contents position information for connecting to contents to be provided
to a mobile communication terminal via a wireless Internet;

(A-3) generating CP connection menus and a directory menu which is a menu provided via the mobile communication terminal and
connecting the contents connection point to the CP connection menus; and

(A-4) forming a segment for providing the contents to the mobile communication terminal according to a prescribed regulation
and selectively connecting the directory menu and the CP connection menus to the segment.

US Pat. No. 9,491,480

MOTION VECTOR ENCODING/DECODING METHOD AND APPARATUS USING A MOTION VECTOR RESOLUTION COMBINATION, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a motion vector of a current block, the apparatus comprising:
a resolution combination determiner configured to select a set of motion vector resolution candidates, to be applied to an
image area in which the current block is located, from among a plurality of sets of motion vector resolution candidates, each
set of the plurality of sets including one or more motion vector resolution candidates, wherein at least one of the plurality
of sets of motion vector resolution candidates includes a plurality of motion vector resolution candidates; and

a motion information encoder configured to encode, into a bitstream, motion vector data determined for the motion vector of
the current block according to a code table corresponding to the selected set of motion vector resolution candidates,

wherein each motion vector resolution is a resolution of each motion vector,
wherein the code table is selected from a plurality of code tables and each of the plurality of code tables includes a plurality
of codewords corresponding to a plurality of motion vectors, and

wherein the plurality of motion vectors included in each of the plurality of code tables corresponds to each of the plurality
of sets of motion vector resolution candidates further comprising an encoding cost calculator configured to calculate an encoding
cost of the current block according to the one or more motion vector resolutions included in each set of the plurality of
sets of motion vector resolution candidates, wherein the resolution combination determiner is configured to select the set
of motion vector resolution candidates having the lowest encoding cost among the encoding costs calculated for the plurality
of sets of the motion vector resolution candidates.

US Pat. No. 9,462,292

METHOD AND APPARATUS FOR VIDEO ENCODING/DECODING USING IMPROVED MERGE

SK TELECOM CO., LTD., Se...

1. A video decoding method, comprising:
extracting a merge flag and a merge index from a bitstream;
when the merge flag indicates a merge mode,
checking for whether predetermined candidate adding conditions are satisfied, and
adding into a merge candidate set including the merge candidates corresponding to neighboring blocks of a current block, a
combined bi-predictive motion parameter, the combined bi-predictive motion parameter generated by combining a list 0 motion parameter of a first available candidate block and a list 1 motion parameter of a second available candidate block, when the predetermined candidate adding conditions are satisfied;
and

generating a predicted block of the current block by using a motion parameter corresponding to a merge candidate selected
from the merge candidate set, the merge candidate selected by the extracted merge index,

wherein the merge candidate set is generated based on a maximum number of the merge candidates, the maximum number of the
merge candidates decided using information on the number of the merge candidates included in the bitstream.

US Pat. No. 9,386,324

IMAGE ENCODING/DECODING APPARATUS AND METHOD USING MULTI-DIMENSIONAL INTEGER TRANSFORM

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding an intra block in a square shape, the apparatus comprising:
a rectangular encoder configured to
decompose the intra block into a plurality of rectangular subblocks based on an intra prediction direction of an intra prediction
mode of the intra block, and

sequentially encode the plurality of rectangular subblocks according to the same intra prediction mode as the intra prediction
mode of the intra block to generate a rectangularly encoded bitstream of the intra block by

predicting a rectangular subblock of the plurality of rectangular subblocks according to the intra prediction mode of the
intra block by using neighboring pixels adjacent to the rectangular subblock to generate a rectangular predicted subblock
corresponding to the rectangular subblock, and

encoding the rectangular subblock by using the rectangular predicted subblock, wherein one or more encoded pixels in the encoded
rectangular subblock are used as part of neighboring pixels for predicting at least one non-encoded rectangular subblock adjacent
to the encoded rectangular subblock;

a square encoder configured to encode the intra block according to the intra prediction mode of the intra block to generate
a squarely encoded bitstream of the intra block; and

an encoding selector configured to
select one of the square encoder and the rectangular encoder to generate an encoded bitstream of the intra block by encoding
the intra block into either the squarely encoded bitstream or the rectangularly encoded bitstream, and

encode mode information on the intra prediction mode and a block mode of the intra block, wherein the block mode represents
the selected encoded bitstream among the squarely encoded bitstream and the rectangularly encoded bitstream.

US Pat. No. 9,367,742

APPARATUS AND METHOD FOR MONITORING OBJECT FROM CAPTURED IMAGE

SK TELECOM CO., LTD., Se...

1. An object monitoring apparatus, comprising:
an image receiver configured to receive at least one frame of captured images;
an edge image generator configured to generate an edge image by detecting edges of objects appearing in the frame;
a reference image generator configured to generate a reference image by detecting a part corresponding to a background in
the frame to thereby define the detected part as a background edge, the reference image generated by repeatedly detecting
as many as or more than a predetermined number an edge commonly appearing over a plurality of the frames;

a candidate object extractor configured to extract one or more candidate object pixels by comparing the edge image with the
reference image, and to extract a candidate object by grouping the extracted candidate object pixels into the candidate object;
and

an object-of-interest determiner configured to determine whether the candidate object is an object-of-interest based on a
size of the candidate object and a duration time of detection of the candidate object.

US Pat. No. 9,398,298

APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING PREDICTABILITY OF INTRA-PREDICTION MODE

SK TELECOM CO., LTD., Se...

1. An apparatus for decoding a video, the apparatus comprising:
a mode information extractor configured to extract mode information on an intra-prediction mode of a current block from encoded
data;

a prediction mode determiner configured to
derive a set of candidate intra-prediction modes including at least three candidate intra-prediction modes, based on information
on neighboring blocks adjacent to the current block, and

determine a candidate intra-prediction mode selected from the derived set of candidate intra-prediction modes as the intra-prediction
mode of the current block without comparing mode numbers of candidate intra-prediction modes included in the derived set each
other, when the mode information indicates a first encoding mode;

a prediction mode extractor configured to determine the intra-prediction mode of the current block by using a prediction mode
identification information, when the mode information indicates a second encoding mode and includes the prediction mode identification
information; and

a decoder configured to decode the encoded data to produce a residual block, and reconstruct the current block by adding the
produced residual block to a prediction block predicted based on the intra-prediction mode of the current block determined
by either the prediction mode determiner or the prediction mode extractor.

US Pat. No. 9,311,719

IMAGE MONITORING APPARATUS FOR ESTIMATING GRADIENT OF SINGLETON, AND METHOD THEREFOR

SK TELECOM CO., LTD., Se...

1. An image monitoring apparatus, comprising:
a singleton selector configured to select at least one singleton from among a plurality of objects in an acquired image;
a single foreground image generator configured to generate a single foreground image of the singleton;
an eigenvector extractor configured to extract an eigenvector of a foreground singleton contained in the single foreground
image by using at least one selected from the group consisting of (i) a centroid of the foreground singleton, (ii) the number
of pixels of the foreground singleton and (iii) coordinate values of the pixels;

a vanishing point location calculator configured to
generate a reference vector by connecting a predetermined point in the acquired image to the centroid of the foreground singleton,
and

determine the predetermined point as a vanishing point when the predetermined point minimizes an angle between the reference
vector and the eigenvector; and

a gradient determiner configured to
determine a gradient of the foreground singleton using the vanishing point, and
correct an inclination and a size of a bounding box of the foreground singleton.

US Pat. No. 9,331,976

METHOD OF REQUEST ROUTING RE-DIRECTION WITH LOOP DETECTION AND PREVENTION

ELECTRONICS AND TELECOMMU...

1. A computer implemented method of request routing redirection, comprising;
receiving, from a user terminal, a domain name system (DNS) request among a plurality of CDNs connected by CDN interconnection
(CDNi), the request including a list of CDN-provider-identifications (IDs) of higher CDNs of a first content delivery network
(CDN);

determining, by a processor, whether the request is processable for routing; and
in response to detection the request is not processable, redirecting the request, while preventing a loop of request routing
according to the list.

US Pat. No. 9,326,002

METHOD AND AN APPARATUS FOR DECODING A VIDEO

SK TELECOM CO., LTD., Se...

1. A video decoding method using an inter prediction, the method comprising:
obtaining block mode information and residual data from encoded data;
generating a predicted block by performing the inter prediction in the unit of a block identified by the block mode information;
identifying one or more conditions for enabling an inverse quantization and an inverse transform;
skipping both of the inverse quantization and the inverse transform for the obtained residual data to thereby reconstruct
a residual block directly from the obtained residual data, when the one or more identified conditions indicate skipping of
both the inverse quantization and the inverse transform;

inversely quantizing the obtained residual data and skipping the inverse transform for the inversely quantized residual data
to thereby reconstruct a residual block using the inverse-quantized residual data, when the one or more identified conditions
indicate skipping of the inverse transform;

inversely quantizing the obtained residual data and inversely transforming the inversely quantized residual data to thereby
reconstruct a residual block using the inverse transformed residual data, when the one or more identified conditions indicate
non-skipping of both the inverse quantization and the inverse transform; and

adding each pixel value of the predicted block to a corresponding pixel value of the reconstructed residual block.

US Pat. No. 9,275,443

IMAGE-PROCESSING APPARATUS FOR REMOVING HAZE CONTAINED IN VIDEO, AND METHOD THEREFOF

SK TELECOM CO., LTD., Se...

1. An image processing apparatus for removing haze contained in a video, the apparatus comprising:
a haze brightness measurer configured to measure haze brightness in an image containing haze;
a transmission estimator configured to
estimate a blockwise transmission for generating a least final cost function value that is calculated by using a contrast,
an image loss and a time loss of the image, and

estimate a pixelwise transmission based on the estimated blockwise transmission; and
an image reconstructor configured to reconstruct the image by using the measured haze brightness and the estimated pixelwise
transmission.

US Pat. No. 9,271,000

IMAGE-ENCODING APPARATUS AND METHOD, TRANSFORM-ENCODING APPARATUS AND METHOD, APPARATUS AND METHOD FOR GENERATING A TRANSFORM BASE, AND IMAGE-DECODING APPARATUS AND METHOD USED IN SAME

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
an intra prediction error collector configured to collect, for an intra prediction mode of a current block, prediction errors
of respective blocks having the same intra prediction mode as the intra prediction mode of the current block, the respective
blocks being encoded prior to encoding the current block;

a transform base generator configured to generate a transform base for the intra prediction mode based on the collected prediction
errors;

an intra predictor configured to
predict the current block to generate a predicted block by using neighboring pixels of the current block according to the
intra prediction mode of the current block, and

generate a prediction error block of the current block according to a difference between the predicted block and the current
block; and

a transform encoder configured to transform the prediction error block by using the transform base for the intra prediction
mode,

wherein the transform base generator comprises a correlation matrix calculator configured to calculate an autocorrelation
matrix for the intra prediction mode by using (i) each first matrix corresponding to each of the collected prediction errors
of each of the respective blocks for the intra prediction mode and (ii) each transpose matrix of said each first matrix,

wherein the autocorrelation matrix for the intra prediction mode is generated based on an average of respective multiplications
of said each first matrix and said each transpose matrix of said each first matrix, and

wherein the transform base for the intra prediction mode is generated based on the autocorrelation matrix for the intra prediction
mode.

US Pat. No. 9,510,017

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE IN SPATIAL DOMAIN FOR NOISE COMPONENT

SK TELECOM CO., LTD., Se...

1. A video encoding method, comprising:
generating a predicted block by predicting a current block to be encoded;
generating a residual block by subtracting the predicted block from the current block;
encoding, into a bitstream, coding domain information indicating whether the residual block is encoded by a frequency domain
coding or by a spatial domain coding; and

encoding the residual block into the bitstream,
wherein
(1) when the residual block is encoded by the frequency domain coding, the encoding of the residual block comprises
transforming the residual block from a spatial domain into a frequency domain,
quantizing the transformed residual block to generate a transformed and quantized residual block having values in the frequency
domain, and

encoding the transformed and quantized residual block, and
(2) when the residual block is encoded by the spatial domain coding, the encoding of the residual block comprises
skipping a step of transforming the residual block from the spatial domain into the frequency domain,
quantizing the residual block to generate a quantized residual block having values in the spatial domain, and
encoding the quantized residual block.

US Pat. No. 9,509,900

CAMERA CONTROL METHOD, AND CAMERA CONTROL DEVICE FOR SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for controlling cameras, the apparatus comprising:
a database configured to store camera installation information of the cameras including a main camera and one or more sub-cameras;
an image acquisition unit configured to acquire images from the cameras; and
a camera controller configured to
convert image center coordinates of the image acquired by the main camera to three-dimensional coordinates on a three-dimensional
reference coordinate system, by using the camera installation information, wherein the camera installation information includes
(i) camera setup coordinates information and (ii) setup directional information of each camera of the main camera and the
sub-cameras, and the camera installation information is generated based on the three-dimensional reference coordinate system,

select, from among the one or more sub-cameras, at least one sub-camera including the converted three-dimensional coordinates
as field-of-view information, and set up the selected at least one sub-camera as at least one newly selected main camera,

calculate a control value of the newly selected main camera for controlling the newly selected main camera to gaze the three-dimensional
coordinates; and

control the newly selected main camera based on the calculated control value by using the setup directional information so
that the newly selected main camera sets the converted three-dimensional coordinates respectively as corresponding image center
coordinates.

US Pat. No. 9,420,281

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING HIGH-PRECISION FILTER

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus comprising:
a decoding unit configured to extract a quantized frequency-transformed block from a bitstream;
an inverse quantization unit configured to reconstruct a frequency-transformed block based on inversely quantizing the quantized
frequency-transformed block;

an inverse transform unit configured to reconstruct a residual block based on inversely transforming the frequency-transformed
block;

a prediction unit configured to generate a prediction block based on interpolating chroma sub-samples of a reference block
referenced by a motion vector of a current block; and

an addition unit configured to reconstruct the current block based on adding the reconstructed residual block and the prediction
block,

wherein the prediction unit is configured to
calculate non-divided values of a first set of sub-samples by multiplying chroma integer-pixels by integer numerators and
summing the multiplied chroma integer-pixels,

derive the first set of sub-samples by dividing the non-divided values by a common denominator, and
derive a second set of sub-samples by interpolation from the non-divided values of the first set of sub-samples, not from
the first set of sub-samples which have been divided by the common denominator, and then division by the common denominator.

US Pat. No. 9,300,981

INTRA PREDICTION METHOD AND APPARATUS, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding method using an intra prediction, the method comprising:
predicting a current block from a plurality of neighboring blocks of the current block;
decoding a bitstream to thereby extract residual signals;
inversely quantizing the residual signals;
inversely transforming the inversely quantized residual signals; and
adding the inversely transformed residual signals to the predicted pixels in the predicted block,
wherein the prediction of the current block comprises:
calculating a plurality of weighted pixel values of pixels selected in the neighboring blocks by applying weights to the pixels
selected in the neighboring blocks, wherein the weights are decided variably based on a position of a current pixel to be
predicted in the current block; and

deriving a predicted pixel value of the current pixel using the weighted pixel values,
wherein the pixels selected in the neighboring blocks comprise:
a first pixel which is included in an upper neighboring block and located at the same column with the current pixel, and
a second pixel which is included in a left neighboring block and located at the same row with the current pixel.

US Pat. No. 9,173,057

APPARATUS AND METHOD OF MANAGING PERIPHERAL WIRELESS LAN RADIO SIGNAL FOR POSITIONING SERVICE

SK TELECOM CO., LTD., Se...

1. An apparatus for managing one or more access points (APs), the apparatus comprising:
an information receiver configured to receive one or more peripheral wireless local area network (LAN) radio signals from
a service provider AP, wherein the service provider AP is located at a preset location in lattice cells, and the one or more
peripheral wireless LAN radio signals are scanned by the service provider AP; and

an additional storage unit configured to
match individual cell IDs of the lattice cells with AP identification information of each of the one or more peripheral wireless
LAN radio signals for each of lattice cells, and

store (i) information of the matched lattice cell and (ii) the AP identification information of each of the one or more peripheral
wireless LAN radio signals in a database,

wherein the lattice cells are identified by corresponding individual cell IDs and the AP identification information is stored
by using location information of the service provider AP as reference location information.

US Pat. No. 9,319,714

INTRA PREDICTION METHOD AND APPARATUS, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus using an intra prediction, the apparatus comprising:
an intra predictor configured to predict a current block from a plurality of neighboring blocks of the current block;
a subtractor configured to generate residual signals by subtracting predicted pixels in the predicted block from pixels in
the current block;

a transformer configured to transform the residual signals into a frequency domain;
a quantizer configured to quantize the transformed residual signals; and
an encoder configured to encode the quantized residual signals into a bitstream,
wherein the intra predictor comprises:
a weighted pixel calculator configured to calculate a plurality of weighted pixel values of pixels selected in the neighboring
blocks by applying weights to the pixels selected in the neighboring blocks, wherein the weights are decided variably based
on a position of a current pixel to be predicted in the current block; and

a pixel predictor configured to derive a predicted pixel value of the current pixel using the weighted pixel values,
wherein the pixels selected in the neighboring blocks comprise:
a first pixel which is included in an upper neighboring block and located at the same column with the current pixel, and
a second pixel which is included in a left neighboring block and located at the same row with the current pixel.

US Pat. No. 9,408,176

LOCATION AND STATE INFORMATION PROVIDING/INQUIRING SYSTEM USING WLAN/WPAN COMMUNICATION, LOG INFORMATION PROVIDING/INQUIRING SYSTEM AND METHOD, SERVICE SERVER AND CUSTOMER TERMINAL, LOCATION AND STATE PROVIDING/INQUIRING METHOD

SK TELECOM CO., LTD., Se...

1. A mobile terminal device for positioning, comprising:
a wireless local area network (WLAN)/wireless personal area network (WPAN) communication unit configured to acquire identification
information of one or more WLAN/WPAN communication modules of one or more other terminal devices adjacent to the mobile terminal;

a request unit configured to transmit the identification information of the WLAN/WPAN communication modules to a service server
to

inquire whether the other terminal devices subscribe a service subscribed by the mobile terminal device, and
request location and state information of the other terminal devices that subscribe the service, wherein the location and
state information of the other terminal devices is inquired to a positioning server by the service server, and searched by
interworking with the positioning server; and

a user interface unit configured to
receive the location and state information of the other terminal devices from the service server and
display the location and state information of the other terminal devices that subscribe the service on a screen.

US Pat. No. 9,348,032

DATABASE UPDATE METHOD AND APPARATUS FOR LOCATING A PCELL

SK PLANET CO., LTD., Seo...

1. A database update apparatus for pCell location determination, the apparatus comprising:
a database configured to store a plurality of pCell parameters extracted from signal of base stations associated with grid
cells of mobile communication network that are classified by pCell ID;

a DB collection unit configured to collect log data of WLAN signals from a mobile communication terminal having a WLAN module,
wherein the WLAN module performs a communication with an AP (Access Point) using the WLAN signals;

an information extraction unit configured to extract WLAN parameters from the log data; and
a DB update unit configured to update the database by storing the extracted WLAN parameters with pCell ID as the pCell parameters
on a corresponding grid cell in the database,

wherein the pCell ID is identified based on PSC (Primary Scrambling Code) and a base station sector number (Ref_PN) for a
base station located in an area, and

wherein the pCell parameters includes at least one of system ID, network ID, base station ID, the base station sector number
(Ref_PN), pilot phase and signal strength of in the base station sector number (Ref_PN), a neighboring base station sector
number (measurement PN), and pilot phase in the measurement PN.

US Pat. No. 9,462,278

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING VARIABLE SIZED MACROBLOCKS

SK TELECOM CO., LTD., Se...

1. A method performed by an apparatus of encoding a video in the unit of blocks, the method comprising:
determining a maximum block size to be used for encoding an image;
encoding size information for indicating the determined maximum block size; and
encoding the image using the determined maximum block size,
wherein the size information includes a first information on a minimum block size, and a second information on a difference
between the minimum block size and the determined maximum block size,

wherein the second information has a value of log 2 (MB size/X), where MB size is the determined maximum block size and X
is the minimum block size.

US Pat. No. 9,491,132

SYSTEM AND METHOD FOR PROVIDING PUSH SERVICE FOR REDUCING NETWORK LOADS

SK TELECOM CO., LTD., Se...

1. A push service device, comprising:
a service provider (SP) interworking unit configured to receive a push message from a service providing device;
a first client interworking unit configured to transmit the received push message to a client device;
a second client interworking unit; and
a controller comprising a processor, the processor configured to
hold, when the first client interworking unit failed to transmit the received push message to the client device, a transmission
of the received push message,

perform, when another push message to be transmitted to the client device is received through the SP interworking unit or
when a keep-alive message is received from the client device through the first client interworking unit, a reconnection with
the client device through the first client interworking unit, and

transmit, to the client device, the held push message through the first client interworking unit,
wherein, when a failure of the transmission is caused by the first client interworking unit,
the processor is configured to back up the received push message and the setting information of the first client interworking
unit in the second client interworking unit, and

the second client interworking unit is configured to
store the backed-up push message and the backed-up setting information,
perform a reconnection with the client device based on the backed-up setting information, and
transmit, when the second client interworking unit is connected to the client device, the backed-up push message to the client
device.

US Pat. No. 9,264,732

METHOD AND AN APPARATUS FOR DECODING A VIDEO

SK TELECOM CO., LTD., Se...

1. A method for decoding a residual block, the method comprising:
obtaining residual data from encoded data;
identifying one or more conditions for enabling an inverse quantization and an inverse transform;
skipping both of the inverse quantization and the inverse transform for the obtained residual data to thereby reconstruct
a residual block directly from the obtained residual data, when the one or more identified conditions indicate skipping of
both the inverse quantization and the inverse transform;

inversely quantizing the obtained residual data and skipping the inverse transform for the inversely quantized residual data
to thereby reconstruct a residual block using the inverse-quantized residual data, when the one or more identified conditions
indicate skipping of the inverse transform; and

inversely quantizing the obtained residual data and inversely transforming the inversely quantized residual data to thereby
reconstruct a residual block using the inverse transformed residual data, when the one or more identified conditions indicate
non-skipping of both the inverse quantization and the inverse transform.

US Pat. No. 9,125,065

APPARATUS AND METHOD FOR SUPPORTING SIMULTANEOUS DATA TRANSMISSION SERVICE OVER MULTIPLE NETWORKS

SK TELECOM CO., LTD., Se...

9. A method of operating a transmitting device, the method comprising:
selecting partial data divided from data to be transmitted over each of access networks based on a data transmission rate
of each of the access networks;

obtaining a preset period time in accordance with each of the access networks;
selecting, on the preset period time, two or more partial data among the selected partial data whenever the period time arrives;
respectively inserting identification information for measuring a data reception time interval into the selected two or more
partial data;

transmitting the selected two or more partial data to a receiving device through a particular access network; and
acquiring transmission state information of the particular access network based on at least one of a data transmission time
interval between the two or more partial data and a data reception time interval measured by the receiving device based on
the identification information inserted into the transmitted two or more partial data.

US Pat. No. 9,606,216

INDOOR POSITIONING SYSTEM, AND DEVICE AND METHOD THEREFOR

SK TELECOM CO., LTD., Se...

1. A terminal device for indoor positioning, the terminal device comprising:
a communication module configured to receive access point (AP) radio environment information from one or more APs;
a memory module configured to store the AP radio environment information in a preset number of frame areas, the AP radio environment
information being stored in order of reception; and

a terminal control module configured to
calculate an estimated location of the terminal device based on the order of the AP radio environment information stored in
the preset number of frame areas, and

verify the number of AP radio environment information updated or deleted,
wherein the terminal control module further comprises
a positioning requester configured to
transmit a location information request signal including the AP radio environment information to a positioning apparatus when
the verified number of the AP radio environment information previously stored in the preset number of frame areas is less
than a predetermined number, and

receive a location information response signal corresponding to the location information request signal from the external
positioning apparatus.

US Pat. No. 9,232,234

VIDEO CODING DEVICE, VIDEO CODING METHOD THEREOF, VIDEO DECODING DEVICE, AND VIDEO DECODING METHOD THEREOF

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a block mode determiner configured to determine a block mode of a current block to be encoded, the block mode of the current
block being determined as one of prediction modes including an inter mode and an intra mode;

a non-coded intra (NCI) block intra encoder configured to encode an NCI block located at a first position adjacent to the
current block, when the block mode of the current block is the intra mode; and

a current block intra encoder configured to encode the current block by performing an intra prediction after the NCI block
located at the first position adjacent to the current block is encoded, when the block mode of the current block is the intra
mode.

US Pat. No. 9,336,577

IMAGE PROCESSING APPARATUS FOR REMOVING HAZE CONTAINED IN STILL IMAGE AND METHOD THEREOF

SK TELECOM CO., LTD., Se...

1. An image processing apparatus for removing haze from an image, the apparatus comprising:
a haze brightness measurer configured to measure haze brightness in the image;
a transmission estimator configured to
estimate a blockwise transmission based on a final cost function value calculated by a contrast and an image loss of the image,
and

estimate a pixelwise transmission by using the blockwise transmission; and
an image reconstructor configured to generate a reconstructed image by using the haze brightness and the pixelwise transmission.

US Pat. No. 9,118,921

IMAGE ENCODING/DECODING METHOD AND DEVICE

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus comprising:
an encoding information decoder configured to
reconstruct a skip information indicating whether a block to be decoded in an image is a skip block by decoding a bitstream,
and

reconstruct either a skip motion information of the block, or an intra or inter prediction information of the block and a
transform information of the block by decoding the bitstream, according to the skip information; and

a video decoder configured to either reconstruct the block based on the skip motion information or reconstruct the block based
on both the prediction information and a residual signal information reconstructed by decoding the bitstream based on the
transform information,

wherein the encoding information decoder is configured to reconstruct the transform information which includes partition information
related to partitioning the block into subblocks by using a tree structure,

wherein the partition information is reconstructed by
reconstructing a side information containing an information on a maximum number of layers and an information on a minimum
subblock size by decoding the bitstream,

reconstructing a flag indicating whether a node for each layer from a highest layer toward the lowest layer is partitioned
by decoding the bitstream based on the side information, and

identifying a node which is not further partitioned, and
wherein the video decoder reconstructs the residual signal information of a subblock corresponding to the node which is not
further partitioned.

US Pat. No. 9,100,782

LOCATION AND STATE INFORMATION PROVIDING/INQUIRING SYSTEM USING WLAN/WPAN COMMUNICATION, LOG INFORMATION PROVIDING/INQUIRING SYSTEM AND METHOD, SERVICE SERVER AND CUSTOMER TERMINAL, LOCATION AND STATE PROVIDING/INQUIRING METHOD

SK TELECOM CO., LTD., Se...

1. A service server for providing location and state information of subscriber terminals, comprising:
a subscriber information storage unit for storing identification information of the subscriber terminals and identification
information of one or more wireless local area network (WLAN)/wireless personal area network (WPAN) communication modules
of the subscriber terminals;

an identification information receiving unit for receiving identification information of one or more WLAN/WPAN communication
modules of one or more other terminals from a mobile terminal;

a subscriber information search unit for searching the subscriber information storage unit for subscribers matching with the
identification information of the WLAN/WPAN communication modules; and

a location information transmitting unit for inquiring location and state information of the subscribers searched by interworking
with a positioning server, and transmitting the location and state information to the mobile terminal.

US Pat. No. 9,292,441

CACHE SYNCHRONIZATION SYSTEM, CACHE SYNCHRONIZATION METHOD AND APPARATUS THEREOF

SK TELECOM CO., LTD., Se...

1. A local cache, comprising:
a content storage unit configured to store at least a part of at least one content;
a cache position manager configured to manage position information of one or more local caches; and
a synchronization unit configured to set a synchronization range for the at least one content, and to perform synchronization
of the at least one content such that the at least one content is made available at another local cache located in the set
synchronization range on the basis of the position information of the one or more local caches.

US Pat. No. 9,357,220

ENCODING / DECODING METHOD AND APPARATUS USING A TREE STRUCTURE

SK TELECOM CO., LTD., Se...

1. A decoding method performed by a video decoding apparatus for reconstructing image information divided by a tree structure
from a bitstream, comprising:
decoding the bitstream to reconstruct additional information, including first information on a minimum block size and second
information on a difference between the minimum block size and a maximum block size, wherein the maximum block size is identified
based on the first information on the minimum block size and the second information on the difference; and

reconstructing a partition flag indicating whether or not each block, starting from a block corresponding to an uppermost
layer of the tree structure, is divided into blocks of a lower layer, the block corresponding to the uppermost layer having
the maximum block size identified based on the first and second information, and reconstructing image information of a block
which is not further divided.

US Pat. No. 9,390,200

LOCAL CACHING DEVICE, SYSTEM AND METHOD FOR PROVIDING CONTENT CACHING SERVICE

SK TELECOM CO., LTD., Se...

1. A local caching device, comprising:
a storage unit configured to store some or all contents provided from at least one content provider to at least one user terminal;
a communication interface configured to transmit and receive data between the at least one content provider and the at least
one user terminal; and

a controller configured to
receive, from the content provider, content requested by the user terminal,
register flow information of the requested content when the storage unit stores content which is at least partially identical
to the received content,

wherein the flow information includes source address information indicating a source of content of a cache hit, and destination
address information indicating a destination of content of the cache hit, and

determine whether the requested content is stored in the storage unit when content having the same flow information as the
registered flow information is requested,

wherein the storage unit is further configured to store a content address management table which includes:
a first field configured to record content identification information including at least one of information extracted from
at least part of contents stored in the local caching device and information hashed from at least part of the contents stored
in the local caching device; and

a second field configured to record one or more content URL address information matched with the content identification information,
and

wherein the content identification information includes all of
prefix information having a predetermined length,
a hash value obtained by processing the prefix information using a predetermined hash function, and
metadata of the received content.

US Pat. No. 9,288,495

ADAPTIVE SECONDARY PREDICTION-BASED IMAGE ENCODING/DECODING METHOD, DEVICE AND RECORDING MEDIUM

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a predictor configured to generate a predicted block of a current block by using a first motion vector of the current block;
a first residual block generator configured to generate a first residual block by subtracting the predicted block from the
current block;

an adaptive transform-quantization unit configured to choose to perform one of the following operations to generate a first
quantized block of the current block:

(i) performing a frequency transform of the first residual block into a frequency transformed first residual block and quantizing
the frequency transformed first residual block to generate a frequency domain first quantized block, the first quantized block
of the current block being set as the frequency domain first quantized block, and

(ii) quantizing the first residual block to generate a spatial domain first quantized block of the current block, the first
quantized block of the current block being set as the spatial domain first quantized block of the current block;

a second residual block generator configured to choose to perform one of the following operations to generate a quantized
block to be encoded:

(a) generating a second quantized block by performing a secondary prediction on the spatial domain first quantized block of
the current block by using a spatial domain first quantized block of a reference block, the reference block corresponding
to a neighboring motion vector of the current block, the quantized block to be encoded being set as the second quantized block,
and

(b) skipping the performing of the secondary prediction, the quantized block to be encoded being set as the first quantized
block; and

an encoder configured to
encode the quantized block to be encoded,
encode a first information indicating whether the frequency transform is performed on the first residual block based on the
choosing, and

encode a second information indicating whether the secondary prediction is performed on the spatial domain first quantized
block, when the first residual block has been frequency-transformed into a frequency transformed first residual block.

US Pat. No. 9,363,530

METHOD AND APPARATUS FOR ENCODING/DECODING A MOTION VECTOR BY SELECTING A SET OF PREDICTED CANDIDATE MOTION VECTORS, AND METHOD AND APPARATUS FOR IMAGE ENCODING/DECODING USING THE SAME

SK TELECOM CO., LTD., Se...

1. A video encoding method using an inter-prediction, comprising:
determining a current motion vector of a current block;
predicting the current block by using the determined current motion vector;
determining a candidate predicted motion vector set based on motion information of neighboring blocks of the current block,
wherein the candidate predicted motion vector set has two candidate predicted motion vectors for the current motion vector;

selecting a predicted motion vector of the current motion vector from the two candidate predicted motion vectors in the predicted
candidate motion vector set;

encoding a differential motion vector representing a difference between the current motion vector and the selected predicted
motion vector and a predicted motion vector index indicating the selected predicted motion vector among the two candidate
predicted motion vectors; and

encoding a residual block representing a difference between the predicted block and the current block.

US Pat. No. 9,336,199

AUTOMATIC SENTENCE EVALUATION DEVICE USING SHALLOW PARSER TO AUTOMATICALLY EVALUATE SENTENCE, AND ERROR DETECTION APPARATUS AND METHOD OF THE SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for automatically evaluating sentences over the internet, wherein the apparatus comprises a processor, and
wherein said processor comprises:
an input sentence divider configured to divide a composed input sentence received via the internet into morphemes which are
the smallest units of a sentence;

a part-of-speech tagging section configured to tag parts-of-speech to the morphemes;
a syntax analyzer configured
to analyze, based on the parts-of-speech, a syntax structure of the composed input sentence, and
to output a syntax tree as an analysis result;
a sentence evaluating section configured to evaluate whether the composed input sentence is grammatically correct by using
the syntax tree output by the syntax analyzer; and

an error detector configured
to generate, by using an n-gram, a part-of-speech string for each of the parts-of-speech tagged by the part-of-speech tagging
section,

to detect a syntax error, by analyzing, based on a regular grammar rule and a context free grammar rule, the generated part-of-speech
string, wherein

the regular grammar rule and the context free grammar rule are defined in accordance with a connection relationship, and
the connection relationship is between adjacent parts-of-speech among the parts-of-speech tagged by the part-of-speech tagging
section, and

to provide a corrected draft of the composed input sentence, wherein the corrected draft corrects the detected syntax error.

US Pat. No. 9,264,731

METHOD AND AN APPARATUS FOR DECODING A VIDEO

SK TELECOM CO., LTD., Se...

1. A video decoding method using an inter prediction, the method comprising:
obtaining a differential motion vector and residual data from encoded data;
determining a predicted motion vector;
generating a predicted block by performing the inter prediction based on the differential motion vector and the predicted
motion vector;

identifying one or more conditions for enabling an inverse quantization and an inverse transform;
skipping both of the inverse quantization and the inverse transform for the obtained residual data to thereby reconstruct
a residual block directly from the obtained residual data, when the one or more identified conditions indicate skipping of
both the inverse quantization and the inverse transform;

inversely quantizing the obtained residual data and skipping the inverse transform for the inversely quantized residual data
to thereby reconstruct a residual block using the inverse-quantized residual data, when the one or more identified conditions
indicate skipping of the inverse transform;

inversely quantizing the obtained residual data and inversely transforming the inversely quantized residual data to thereby
reconstruct a residual block using the inverse transformed residual data, when the one or more identified conditions indicate
non-skipping of both the inverse quantization and the inverse transform; and

adding each pixel value of the predicted block to a corresponding pixel value of the reconstructed residual block.

US Pat. No. 9,363,735

DEVICE AND METHOD FOR PROVIDING SIMULTANEOUS DATA TRANSMISSION SERVICE OVER HETEROGENEOUS NETWORKS

SK TELECOM CO., LTD., Se...

1. A transmission device for providing a simultaneous data transmission service over two or more networks in a heterogeneous
network, the transmission device comprising:
a controller configured to divide data to be transmitted into two or more partial data; and
a communication unit configured to transmit the divided two or more partial data to a reception device through at least one
of the two or more networks,

wherein the controller is configured to
insert, into first partial data of the divided two or more partial data, network access information of the reception device
corresponding to a first network of the two or more networks and virtual network access information corresponding to the transmission
device or the reception device, and

insert, into second partial data of the divided two or more partial data, network access information of the reception device
corresponding to a second network of the two or more networks and virtual network access information corresponding to the
transmission device or the reception device, and

the communication unit is configured to
transmit the first partial data with the corresponding inserted information to the reception device through the first network,
and

transmit the second partial data with the corresponding inserted information to the reception device through the second network,
wherein the first and second networks are different networks of heterogeneous networks, and

wherein when problem occurrence of the first network is identified, the controller is configured to switch transmission of
the first partial data from the first network to the second network, by replacing the network access information of the reception
device corresponding to the first network previously inserted into the first partial data with the network access information
of the reception device corresponding to the second network.

US Pat. No. 9,674,520

METHOD AND APPARATUS FOR EFFECTIVE ENCODING/DECODING USING DETAILED PREDICTIVE UNIT

SK TELECOM CO., LTD., Se...

1. An apparatus for decoding images, comprising: a decoder configured to decode one or more quantized transform blocks from
a bitstream, and extract prediction unit (PU) mode information indicating a prediction unit (PU) mode of a current coding
unit (CU) among a plurality of PU modes relating to types of partition of the current CU into PUs,
wherein the plurality of PU modes includes a horizontally longer made and a vertically longer mode;
an inverse quantizer configured to inversely quantize the quantized transform blocks to generate transform blocks;
an inverse transformer configured to inversely transform the transform blocks to reconstruct a residual block of the current
CU;

a predictor configured to generate one or more predicted block of the current CU by predicting each PU within the current
CU based on the PU mode; and

an adder configured to add the reconstructed residual block and the generated predicted block,
wherein the predictor generates the predicted blocks by using motion information selected from a plurality of merge candidates
corresponding to neighboring blacks, based on a merge index, and the merge candidates are generated by predetermined positions
and priorities corresponding to the positions,

wherein the merge candidates are generated in consideration of a position of the current PU in the current CU and the PU mode,
wherein the merge candidates include at least one of a left block A, an upper block B, an upper-right block C, a left-lower
block D and an upper-left block E and

the priorities correspond to an order of the left block A, the upper block B, the upper-right block C, the left-lower block
D and the upper-left block E, and

wherein the predictor excludes at least one of the neighboring blocks from the merge candidates when the PU mode corresponds
to the horizontally longer mode or the vertically longer mode and the position of the current PU corresponds to a predetermined
condition, without considering motion information of the at least one of the neighboring blocks.

US Pat. No. 9,602,813

IMAGE ENCODING/DECODING DEVICE AND METHOD, AND REFERENCE PICTURE INDEXING DEVICE AND METHOD

SK TELECOM CO., LTD., Se...

1. An image encoding apparatus comprising:
an image encoder configured to
select a reference picture for predicting a current block from among a plurality of reference picture candidates, the plurality
of reference picture candidates being set in a unit of (i) the current block or (ii) an image area in which the current block
is located,

determine a motion vector of the current block, the motion vector of the current block being used for identifying a predicted
block of the current block in the selected reference picture, and

encode the current block by encoding, into a bitstream, (i) a reference index of the selected reference picture and (ii) information
on the determined motion vector; and

a reference picture indexer configured to assign, based on an indexing order of the plurality of reference picture candidates,
the reference index to the selected reference picture for identifying the selected reference picture from among the plurality
of reference picture candidates, the indexing order being determined adaptively in the unit of (i) the current block or (ii)
the image area,

wherein the indexing order is determined, irrespective of a temporal order of the plurality of reference picture candidates.

US Pat. No. 9,351,008

ENCODING / DECODING METHOD AND APPARATUS USING A TREE STRUCTURE

SK TELECOM CO., LTD., Se...

1. A method performed by a video encoding apparatus for encoding image information using a tree structure, the method comprising:
encoding additional information including first information on a minimum block size and second information on a difference
between the minimum block size and a maximum block size; and

encoding a partition flag indicating whether each block, starting from a block corresponding to an uppermost layer of the
tree structure, is divided into blocks of a lower layer, and encoding image information of a block which is not further divided,
wherein the block corresponding to the uppermost layer has the maximum block size,

wherein the first and second information are used for identifying the maximum block size.

US Pat. No. 9,513,138

METHOD, SYSTEM AND TERMINAL FOR PROVIDING MAP INFORMATION

SK TELECOM CO., LTD., Se...

1. A method of providing map information by an apparatus, the method comprising:
upon initial execution of a map application, receiving streaming image map-based map information corresponding to a current
location of the apparatus, the streaming image map-based map information being received from a service device in a streaming
scheme;

displaying the received streaming image map-based map information as a streaming image map;
detecting a movement of the apparatus along a predetermined route; and
displaying map information varying with the movement along the predetermined route using pre-stored embedded vector map-based
map information by switching into an embedded vector map-based operation based on the detected movement.

US Pat. No. 9,231,922

CLOUD STORAGE SYSTEM, DATA ENCRYPTION PROCESSING DEVICE AND DATA ENCRYPTION METHOD IN CLOUD STORAGE SYSTEM

SK TELECOM CO., LTD., Se...

1. A data encryption processing device of a cloud storage system, comprising:
a priority manager configured to
manage a priority to encrypt data of each of a plurality of cloud storage modules based on information regarding whether the
plurality of the cloud storage modules is subject to encryption processing, and

update the priority of said each of the plurality of the cloud storage modules, based on
a counter value for encryption requests for said each of the plurality of the cloud storage modules, and
the information regarding whether said each of the plurality of the cloud storage modules is subject to the encryption processing;
and

an encryption requester configured to
select at least one cloud storage module among the plurality of the cloud storage modules based on the priority to encrypt
data of the plurality of cloud storage modules managed by the priority manager, and

transfer data to the selected at least one cloud storage module to request the selected at least one cloud storage module
to perform encryption of the transferred data, in response to a data encryption request.

US Pat. No. 9,736,475

METHOD AND APPARATUS FOR GENERATING A REFERENCE FRAME AND METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING THE SAME

SK Telecom Co., Ltd., Se...

1. A method performed by a video encoding apparatus for encoding pixels in an image, the method comprising:
encoding an offset to be applied to a reference frame;
generating predicted pixels of the pixels in the image, based on interpolating pixels in the reference frame and then adding
the offset to the interpolated pixels; and

encoding residual signals that are differences between the pixels in the image and the predicted pixels, by determining an
encoding scheme of the residual signals,

wherein the encoding of the residual signals comprises:
skipping both transform and quantization for the residual signals and thereby encoding the residual signals for which both
transform and quantization are skipped, when the determined encoding scheme of the residual signals corresponds to skipping
of both transform and quantization;

skipping transform and performing quantization for the residual signals and thereby encoding the quantized residual signals
for which transform is skipped, when the determined encoding scheme corresponds to skipping of transform; and

performing transform and quantization for the residual signals and thereby encoding the transformed and quantized residual
signals when the determined encoding scheme corresponds to skipping neither transform nor quantization.

US Pat. No. 9,596,048

METHOD FOR SHARING OPTICAL FIBER FOR CLOUD-BASED WIRED AND WIRELESS ACCESS NETWORK, AND SYSTEM AND APPARATUS FOR SAME

SK TELECOM CO., LTD., Se...

6. A method performed by the system for delivering uplink signals and downlink signals between a plurality of donor units
and a plurality of remote units in cloud-based radio access network (C-RAN), the method comprising:
receiving, by the centralization device, a plurality of downlink signals from the plurality of donor units at low transmission
rates;

processing, by the centralization device, a part of the plurality of downlink signals to generate a plurality of summing signals,
each summing signal carrying at least two downlink signals;

converting, by the centralization device, the plurality of summing signals at different wavelengths to generate a plurality
of converted optical signals of high transmission rates, and convert a rest of the plurality of downlink signals at different
wavelengths to generate a plurality of converted optical signals;

multiplexing, by the centralization device, the plurality of converted optical signals to generate a multiplexed optical signal;
distributing, by the centralization device, the multiplexed optical signal into the optical ring network;
receiving, by each distribution device, the multiplexed optical signal from the optical ring network;
demultiplexing, by each distribution device, the multiplexed optical signal to generate the plurality of converted optical
signals;

processing, by each distribution device, optical signal of the wavelength associated with the summing signal to generate at
least two downlink signals; and
transmitting, by each distribution device, a plurality of downlink signals to the respective subset of the plurality of remote
units.

US Pat. No. 9,479,791

IMAGE-FILTERING METHOD AND APPARATUS, AND ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus comprising:
a decoder configured to
decode information on a size of a current block from encoded data, to thereby variably determine the size of the current block,
wherein the current block is a macroblock in which a prediction type is designated among an inter-prediction type and an intra-prediction
type, and the variably determined size of the current block includes a size larger than 16×16,

decode, from the encoded data, transform information for identifying one or more transform blocks in the current block having
the determined size, wherein a size of each of the transform blocks is variably determined depending on both the size of the
current block and the transform information, and

reconstruct, from the encoded data, each of the transform blocks in the current block;
an inverse transformer configured to reconstruct a residual block corresponding to each of the transform blocks by inversely
transforming the transform blocks in units of the size of each of the transform blocks;

a predictor configured to generate a predicted block by using an intra-prediction;
an adder configured to reconstruct the current block by adding the residual block to the predicted block; and
a filter configured to identify transform boundaries between the transform blocks in the reconstructed current block by using
the size of each of the transform blocks determined based on both the size of the current block and the information on the
transform type, and then perform deblocking-filtering on at least part of the transform boundaries,

wherein the decoder is configured to identify whether the current block is divided into a plurality of blocks and then recursively
identify whether each of divided blocks is further divided, based on the transform information, to thereby identify blocks
which are not further divided as the transform blocks,

wherein the decoder is configured to reconstruct each of the transform blocks by scanning transform coefficients corresponding
to each of the transform blocks according to a scanning pattern corresponding to each of the transform blocks, and

wherein the scanning pattern is determined based on the size of each of the transform blocks.

US Pat. No. 9,451,285

INTER-PREDICTION METHOD AND VIDEO ENCODING/DECODING METHOD USING THE INTER-PREDICTION METHOD

SK TELECOM CO., LTD., Se...

1. A video decoding method using inter-prediction, comprising:
decoding a first picture, wherein the first picture serves as a random access picture and is decoded without referring to
a reference picture which has already decoded; and

decoding blocks, by using an inter-prediction, included in a second picture, which is decoded after the first picture and
displayed before the first picture, by using a plurality of reference pictures,

wherein the decoding of the blocks included in the second picture is performed based on reference picture information included
in a bitstream, the reference picture information representing the reference pictures used for decoding the second picture
among reference pictures including one or more reference pictures decoded before the first picture,

wherein, the one or more reference pictures decoded before the first picture are adaptively deleted from a memory based on
the reference picture information,

when the reference picture information represents that the one or more reference pictures decoded before the first picture
are used for decoding the second picture, the one or more reference pictures decoded before the first picture are deleted
from the memory after decoding at least the second picture, and

wherein the memory includes a reference picture list 0 into which past reference pictures displayed before the second picture to be decoded are inserted and a reference picture
list 1 into which future reference pictures displayed after the second picture to be decoded are inserted, and

the reference picture list 0 is allowed to include, in addition to the past reference pictures, one or more future reference pictures which are inserted
into the reference picture list 1.

US Pat. No. 9,070,179

METHOD AND APPARATUS FOR SELECTIVELY ENCODING/DECODING SYNTAX ELEMENTS, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD, Seo...

1. A video decoding method using an inter-prediction, the method comprising:
determining a motion vector of a current block to be decoded in a current picture;
predicting pixels in the current block using the motion vector of the current block;
extracting quantized transform coefficients by decoding a bitstream;
reconstructing residual signals by inversely quantizing and then inversely transforming the quantized transform coefficients;
and

adding the predicted pixels and the reconstructed residual signals which correspond to the predicted pixels,
wherein the determination of the motion vector of the current block comprises:
obtaining a flag by decoding the bitstream, the flag indicating one among a plurality of modes for determining the motion
vector of the current block; and

when the flag indicates a first mode among the plurality of modes, performing a process comprising:
deriving a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block,
selecting a candidate motion vector from the set of candidate motion vectors,
determining the selected candidate motion vector to be a predicted motion vector of the current block, and
reconstructing the motion vector of the current block by adding the predicted motion vector of the current block to a differential
vector decoded from the bitstream.

US Pat. No. 9,609,324

IMAGE ENCODING/DECODING METHOD AND DEVICE USING COEFFICIENTS OF ADAPTIVE INTERPOLATION FILTER

SK TELECOM CO., LTD., Se...

1. An image encoding method, the method comprising:
encoding a filter flag which indicates whether default interpolation filter coefficients are used as interpolation filter
coefficients for a current image unit to predict one or more blocks in the current image unit, wherein the default interpolation
filter coefficients are either (i) interpolation filter coefficients used in an image unit preceding the current image unit
or (ii) interpolation filter coefficients set in a larger image unit to which the current image unit belongs to;

when the default interpolation filter coefficients are not used for the current image unit, determining interpolation filter
coefficients for the current image unit and encoding an information on the interpolation filter coefficients for the current
image unit into a bit stream wherein, when the default interpolation filter coefficients are used as the interpolation filter
coefficients for the current image unit, the information on the interpolation filter coefficients for the current image unit
is not encoded into the bit stream;

interpolating pixels in a reference frame for predicting a current block in the current image unit by using the interpolation
filter coefficients for the current image unit;

generating a prediction block of the current block from the interpolated pixels in the reference frame; and
encoding the current block into the bit stream by using the prediction block.

US Pat. No. 9,553,917

SERVER, DEVICE AND RECORDING MEDIUM FOR HTTP FILE TRANSFER DURING CHATTING SESSION ESTABLISHED BY ANOTHER PROTOCOL

SK TELECOM CO., LTD., Se...

1. A message server for transferring a file by using a second protocol during a chatting session established by a first protocol,
the message server comprising:
a server transceiver unit, implemented by one or more processors and/or application-specific integrated circuits (ASICs),
configured to transmit and receive data; and

a server control unit, implemented by one or more processors and/or application-specific integrated circuits (ASICs), configured
to

establish the first protocol for the chatting session between a transmitting terminal device and a receiving terminal device,
provide a chatting service via the established chatting session of the first protocol through the server transceiver unit,
and

transmit file link information via the first protocol to the receiving terminal device through the server transceiver unit,
wherein the file link information is received from the transmitting terminal device through the server transceiver unit after
the second protocol session is established between the transmitting terminal device and the receiving terminal device, and
the transmitting terminal device uploads a file to the content server via the second protocol,

wherein the file link information is associated with a file uploaded using the second protocol to a content server by the
transmitting terminal device,

the first protocol and the second protocol is different protocol each other,
the second protocol is separately established while the first protocol for the chatting session is continuously established,
and

the second protocol is established to upload the file from the transmitting terminal device to the content server, and download
the uploaded file from the content server to the receiving terminal device.

US Pat. No. 9,532,065

IMAGE-FILTERING METHOD AND APPARATUS, AND ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus for decoding a current block larger than 16×16, the apparatus comprising:
a decoder configured to
extract information on a size of the current block from encoded data and thereby variably decide the size of the current block
and a size of a transformed/quantized residual block which is same as the size of the current block, wherein the current block
is a macroblock in which a prediction type is designated among an inter-prediction type and an intra-prediction type, and
the variably decided size of the current block includes a size larger than 16×16, and

extract information on a transform type for identifying transform blocks within the transformed/quantized residual block by
decoding the encoded data, wherein the decoder variably determines a transform size corresponding to a size of each transform
block depending on the size of the current block and the information on the transform type and thereby allows the transformed/quantized
residual block to be divided into a plurality of transform blocks having various transform sizes,

reconstruct, from the encoded data, the transformed/quantized residual block;
an inverse quantizing/transforming unit configured to reconstruct a residual block corresponding to each of the transform
blocks by inverse-quantizing/transforming the transformed/quantized residual block in the unit of the transform sizes of the
transform blocks variably determined based on the size of the current block and the information on the transform type;

a predictor configured to generate a predicted block by an intra-prediction;
an adder configured to reconstruct the current block by adding the reconstructed residual block and the predicted block; and
a filtering unit configured to filter a transform boundary between a transform block in the reconstructed current block and
an adjacent transform block by identifying the transform boundary according to the transform sizes of the transform blocks
variably determined based on the size of the current block and the information on the transform type,

wherein the transformed/quantized residual block is divided into the transform blocks, by identifying whether the transformed/quantized
residual block is divided into a plurality of transform blocks and then recursively identifying whether each of divided transform
blocks is further divided, depending on the information on the transform type, and

wherein the decoder is configured to reconstruct the transformed/quantized residual block by scanning transform coefficients
corresponding to each of the transform blocks in the transformed/quantized residual block according to a scanning pattern
corresponding to each of the transform blocks, wherein the scanning pattern is determined based on the size of each of the
transform blocks.

US Pat. No. 9,258,740

PUSH SERVICE PROVIDING SYSTEM AND METHOD FOR BALANCING MESSAGE LOADS

SK TELECOM CO., LTD., Se...

1. A push service device for balancing message loads, comprising:
a service provider (SP) interworking unit implemented by one or more processors, and configured to connect with a service
providing device;

a controller implemented by one or more processors, and configured to
route a push message received from the service providing device through the SP interworking unit to one or more corresponding
client devices; and

a client interworking unit implemented by one or more processors, and configured to
transmit the push message transferred from the controller to the one or more corresponding client devices,
receive a keep-alive message from at least one of the one or more corresponding client devices, and
transmit a keep-alive configuration message to the one or more corresponding client devices to disperse reception time points
of the keep-alive message for a predetermined transmission period of the keep-alive message when the reception time points
of the received keep-alive message are synchronized.

US Pat. No. 9,154,809

ENCODING/DECODING METHOD AND DEVICE FOR HIGH-RESOLUTION MOVING IMAGES

SK TELECOM CO., LTD., Se...

1. A video decoding method for decoding video data obtained by dividing an input video into a plurality of macroblocks having
various sizes and encoding each of the macroblocks, the method comprising:
decoding macroblock information indicating the size of each of the macroblocks; and
decoding a macroblock based on the macroblock information,
wherein, when the macroblock is intra-predicted, the decoding of the macroblock comprises:
decoding macroblock division information indicating whether the macroblock is divided into subblocks;
predicting a subblock divided from the macroblock based on the macroblock division information to thereby obtain a predicted
subblock;

reconstructing transform coefficients of the subblock based on a scanning pattern to thereby obtain a transformed and quantized
residual subblock;

inverse-quantizing and inverse-transforming the transformed and quantized residual subblock to thereby generate a residual
subblock; and

reconstructing the subblock by adding the residual subblock to the predicted subblock,
wherein the scanning pattern of the subblock is selected among a plurality of scanning patterns, based on an intra prediction
mode used for prediction of the subblock.

US Pat. No. 9,129,282

NEAR FIELD COMMUNICATION APPARATUS AND METHOD FOR SUPPORTING SECURITY MODULES

SK TELECOM CO., LTD., Se...

1. A terminal, comprising:
a socket configured to receive a security module;
an NFC (Near Field Communication) unit configured to communicate with an external reader or another terminal; and
a protocol identifying unit configured to
supply a voltage to the security module, and
identify whether the security module supports a first protocol by transmitting a signal for using the first protocol through
a first contact of the security module and receiving from the security module a first information associated with a protocol
supported by the security module, the first protocol being a signal processing scheme for exchanging data between the NFC
unit and the security module,

wherein the terminal is additionally configured to receive a second information associated with the protocol supported by
the security module through a second contact of the security module, the second contact being different from the first contact,
and

wherein the NFC unit is configured to
receive an information from the security module through the first contact based on the first protocol when the protocol identifying
unit determines that the security module supports the first protocol, and
transmit the received information to the external reader or another terminal.

US Pat. No. 9,100,646

DEVICE AND METHOD FOR IMAGE ENCODING/DECODING USING PREDICTION DIRECTION CONVERSION AND SELECTIVE ENCODING

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a current block using an intra prediction, the apparatus comprising:
a rectangle encoder, upon receiving the current block, configured to sequentially encode the current block by dividing the
current block into rectangular block units and produce a rectangularly encoded bitstream;

a square encoder configured to encode the current block in one or more square block units and produce a squarely encoded bitstream;
and

an encoding selector configured to select one of the rectangle encoder and the square encoder,
wherein the rectangle encoder comprises:
a block divider configured to divide the current block into the rectangular block units and produce a plurality of rectangular
subblocks;

a rectangular prediction unit configured to predict the plurality of rectangular subblocks sequentially and output a plurality
of rectangularly predicted subblocks;

a rectangular subtraction unit configured to subtract the plurality of rectangularly predicted subblocks from the plurality
of rectangular subblocks and generate a plurality of rectangular residual subblocks;

a rectangular transform unit configured to transform the plurality of rectangular residual subblocks into a frequency domain;
a rectangular quantization unit configured to quantize the plurality of transformed rectangular residual subblocks;
a scan unit configured to scan quantized frequency coefficients of the plurality of quantized rectangular residual subblocks;
and

an encoder configured to encode the scanned quantized frequency coefficients and generate the rectangularly encoded bitstream.

US Pat. No. 9,639,937

APPARATUS AND METHOD FOR DETECTING EVENT FROM PLURALITY OF PHOTOGRAPHED IMAGES

SK TELECOM CO., LTD., Se...

1. An event detecting apparatus, comprising:
an image receiver, implemented by one or more processors, configured to receive multiple captured images from multiple cameras;
a rule receiver, implemented by one or more processors, configured to receive
an event rule as a basis for determining the presence or absence of a predetermined event from a synthesized image of the
multiple captured images, and

individual event rules which are converted from the event rule through conversion functions corresponding to coordinate systems
of the multiple cameras;

an object-of-interest extractor, implemented by one or more processors, configured to extract an object-of-interest from the
captured images;

an individual event determiner, implemented by one or more processors, configured to determine whether trace information of
the object-of-interest corresponds to individual events based on the individual event rules;

an event identifier, implemented by one or more processors, configured to
generate inversely converted trace information from the trace information of the object-of-interest through the conversion
functions,

determine whether multiple pieces of the inversely converted trace information comply with the event rule, and
when the multiple pieces of the inversely converted trace information comply with the event rule, identify the object-of-interest
as a single event; and

an event output unit, implemented by one or more processors, configured to generate output information according to the identified
single event.

US Pat. No. 9,571,851

INTER PREDICTION METHOD AND APPARATUS USING ADJACENT PIXELS, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. An inter prediction method for encoding a video image, comprising:
determining a current motion vector of a current block in a current picture;
generating a reference block by interpolating pixels at a position indicated by the current motion vector in a reference picture;
calculating a compensation coefficient by using values of one or more first pixels neighboring the current block in the current
picture and values of one or more second pixels neighboring the reference block in the reference picture;

when a value of the compensation coefficient is not “0”,
generating a changed reference block by applying the compensation coefficient to the reference block, and
setting the changed reference block to be a predicted block of the current block; and
when the value of the compensation coefficient is “0”,
setting the reference block to be the predicted block of the current block,
wherein the one or more first pixels and the one or more second pixels are pixels encoded prior to encoding the current block.

US Pat. No. 9,479,793

METHOD AND APPARATUS FOR ENCODING/DECODING A MOTION VECTOR BY SELECTING A SET OF PREDICTED CANDIDATE MOTION VECTORS, AND METHOD AND APPARATUS FOR IMAGE ENCODING/DECODING USING THE SAME

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus using an inter-prediction, comprising:
a video encoder configured to
determine a current motion vector of a current block,
predict the current block by using the determined current motion vector, and
encode a residual block representing a difference between the predicted block and the current block; and
a motion vector encoder configured to
determine a candidate predicted motion vector set based on motion information of neighboring blocks of the current block,
wherein the candidate predicted motion vector set has two candidate predicted motion vectors for the current motion vector,

select a predicted motion vector of the current motion vector from among the two candidate predicted motion vectors in the
candidate predicted motion vector set, and

encode a differential vector representing a difference between the current motion vector and the selected predicted motion
vector and a predicted motion vector index indicating the selected predicted motion vector among the two candidate predicted
motion vectors.

US Pat. No. 9,380,435

COMMUNICATION SYSTEM, PACKET NETWORK, SUPPLEMENTARY SERVICE CONTROLLER, AND METHOD FOR PROVIDING SUPPLEMENTARY SERVICES

SK TELECOM CO., LTD, Seo...

1. A packet network system for providing supplementary services, said packet network system comprising:
a session controller configured to establish a session connection associated with a basic service between terminals that access
the packet network; and

a supplementary service controller configured to
receive a service profile having information about the supplementary services from a circuit network, wherein the service
profile of the circuit network is transmitted in one way direction from the circuit network to the packet network in order
to allow the packet network system to use the service profile currently used in the circuit network when the packet network
system does not have an independent service profile to provide the supplementary services with the terminals to access the
packet network,

store the received service profile,
check for a supplementary service providable to at least one of the terminals to access the packet network based on the stored
service profile of the circuit network, when there is a request for a session connection between the terminals that access
the packet network, wherein the service profile having, for the at least one of the terminals,

(i) a list of supplementary services associated with the terminal, and
(ii) state information associated with each supplementary service and indicating whether to provide the corresponding supplementary
service or not;

receive supplementary service data of the providable supplementary service from a supplementary service apparatus located
in the circuit network, and

provide the providable supplementary service to the at least one of the terminals by using the received supplementary service
data,

wherein the supplementary service controller is further configured to transmit data required for providing supplementary service
to the supplementary service apparatus, and to request the supplementary service apparatus to provide the supplementary service
to the at least one of the terminals by using the transmitted data, and

wherein the session controller and the supplementary controller are located in the packet network, and when the packet network
system does not have the independent service profile to provide the supplementary services with the terminals to access the
packet network, the supplementary service controller is configured to request the service profile used in the circuit network
by communicating with the supplementary service apparatus located in the circuit network in order to share the service profile
of the circuit network with the packet network.

US Pat. No. 9,363,531

APPARATUS AND METHOD FOR MOTION VECTOR ENCODING/DECODING, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding method using an inter-prediction, the method comprising:
determining a motion vector of a current block to be decoded in a current picture;
predicting pixels in current block using the motion vector of the current block;
extracting quantized transform coefficients by decoding a bitstream;
reconstructing residual signals by inversely quantizing and then inversely transforming the quantized transform coefficients;
and

adding the predicted pixels and the reconstructed residual signals which correspond to the predicted pixels,
wherein the determination of the motion vector of the current block comprises:
obtaining a flag by decoding a bitstream, the flag indicating one among a plurality of modes for determining the motion vector
of the current block; and

when the flag indicates a first mode among the plurality of modes, performing a process comprising:
deriving a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block,
the plurality of neighboring blocks including one or more of blocks located at left, upper, upper right and upper left sides
of the current block in the current picture,

selecting a candidate motion vector from the set of candidate motion vectors,
determining the selected candidate motion vector to be a predicted motion vector of the current block, and
reconstructing the motion vector of the current block by adding the predicted motion vector of the current block to a differential
vector decoded from the bitstream.

US Pat. No. 9,344,731

IMAGE ENCODING AND DECODING APPARATUS AND METHOD

SK TELECOM CO., LTD., Se...

1. An apparatus of decoding a video in the unit of blocks, the apparatus comprising:
a size setting unit configured to
decode information on a picture size of the video and information on available block sizes from a bitstream,
set an initial size of a current block to be decoded to a largest block size determined by the information on the available
block sizes,

determine a location of the current block within a picture,
identify whether the current block is fully located inside the picture, based on the picture size, the size of the current
block and the location of the current block, and

reset the size of the current block to a smaller size among the available block sizes, when the current block is not fully
located inside the picture; and

a decoding unit configured to decode the current block in the reset size.

US Pat. No. 9,264,716

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING SPLIT LAYER

SK TELECOM CO., LTD., Se...

1. A method of decoding a video in unit of blocks at a video decoding apparatus, the method comprising:
extracting and decoding a first information indicating a minimum block size and a second information indicating an enlarging
ratio relative to the minimum block size, from a bitstream encoded by a video encoding apparatus;

setting a maximum block size to a size enlarged from the minimum block size by the enlarging ratio;
setting a size of a square current block to be decoded as the maximum block size and decoding, from the bitstream, partition
information of a square current block having the maximum block size by a tree structure to thereby identify one or more subblocks
in the current block which have sizes equal to or larger than the minimum block size;

decoding a prediction mode information of each of the subblocks from the bitstream, the prediction mode information indicating
whether each of the subblocks is inter-predicted or intra-predicted;

and
reconstructing each of the subblocks in the current block by predicting each of the subblocks according to corresponding prediction
mode information,

wherein the decoding of the partition information comprises:
reconstructing a partition flag indicating whether or not each node of the tree structure, starting from a node of an uppermost
layer corresponding to the current block, is divided into four nodes of a lower layer;

and
identifying blocks corresponding to nodes which are not further divided as the subblocks in the current block.

US Pat. No. 9,215,604

METHOD AND DEVICE FOR UPDATING A DATABASE FOR WIRELESS LAN BASED POSITIONING

SK TELECOM CO., LTD., Se...

1. An apparatus for updating a database for wireless local area network (WLAN) based positioning, the apparatus comprising:
a database configured to store
grid cells divided by pilot cell identifier (pCell ID) and base station-derived environment information, and
WLAN environment information matched to the grid cells;
a grid cell determining unit configured to determine an information-unmeasured grid cell among the grid cells stored in the
database, wherein the information-unmeasured grid cell is a grid cell that has unmeasured information among parameters of
the WLAN environment information matched to the grid cells;

an unmeasured parameter checking unit configured to check an unmeasured parameter in the information-unmeasured grid cell;
a radiowave environment estimating unit configured to generate radiowave environment estimation information by estimating
the unmeasured parameter based on any one of a distance-dependent radiowave strength value application scheme and an adjacent
grid cell-based interpolation scheme; and

a database updating unit configured to update the information-unmeasured grid cell with the radiowave environment estimation
information,

wherein the radiowave environment estimating unit is configured to select adjacent grid cells among peripheral grid cells
of the information-unmeasured grid cell and generate the radiowave environment estimation information including

an estimated medium access control (MAC) address which is a common MAC address shared in the adjacent grid cells of an access
point (AP), when the unmeasured parameter checking unit determined a MAC address of the AP transmitting a WLAN signal and
that the unmeasured parameter is a received signal strength value, and

a first estimated AP signal strength value obtained by estimating the received signal strength value of the AP corresponding
to the common MAC address based on the adjacent grid cell-based interpolation scheme.

US Pat. No. 9,215,462

IMAGE ENCODING/DECODING METHOD AND DEVICE

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
an encoding information decoder configured to
reconstruct a skip information indicating whether a block to be decoded in an image is a skip block by decoding a bitstream,
and

reconstruct either a skip motion information of the block, or an intra or inter prediction information of the block and a
transform information of the block by decoding the bitstream, according to the skip information; and

a video decoder configured to either reconstruct the block based on the skip motion information or reconstruct the block based
on both the prediction information and a residual signal information reconstructed by decoding the bitstream based on the
transform information,

wherein the encoding information decoder is configured to reconstruct the transform information which includes partition information
related to partitioning the block into subblocks by a tree structure,

wherein the partition information is reconstructed by
reconstructing a side information containing a first information on a difference between a maximum subblock size and a minimum
subblock size and a second information on the minimum subblock size by decoding the bitstream,

reconstructing a flag indicating whether each node from a highest layer toward the lowest layer is partitioned into nodes
of a lower layer by decoding the bitstream based on the side information, and

identifying a node which is not further partitioned,
wherein the video decoder reconstructs the residual signal information of a subblock corresponding to the node which is not
further partitioned.

US Pat. No. 9,686,555

VIDEO ENCODING/DECODING APPARATUS AND METHOD USING MOTION INFORMATION CANDIDATE GROUP FOR BATCH MODE

SK TELECOM CO., LTD., Se...

1. A video decoding method, comprising:
reconstructing a skip mode flag, partition type information, motion information, transform subblock partition information,
and quantized transform coefficients by decoding encoded data, the skip mode flag indicating whether a skip mode is used;

reconstructing one or more residual subblocks by inverse-quantizing and inverse-transforming the quantized transform coefficients,
the residual subblocks being identified by the transform subblock partition information;

generating one or more predicted subblocks by predicting one or more subblocks, identified according to the partition type
information, by using the motion information; and

reconstructing a current block by adding the predicted subblocks and the reconstructed residual subblocks,
wherein a batch mode flag, indicating whether a batch mode is used, is further reconstructed for generating the predicted
subblocks, when the skip mode flag does not correspond to the skip mode; and

when the batch mode is used, the predicted subblocks are predicted, using a motion information candidate group which includes
motion information of at least one of spatially adjacent blocks and motion information of a colocated block, and using the
motion information as selection information of the motion information candidate group, the spatially adjacent blocks being
spatially adjacent to the current block and the collocated block being temporally adjacent to the current block,

wherein the at least one of the spatially adjacent blocks and the colocated block has a priority order in the motion information
candidate group, and

wherein the spatially adjacent blocks include
an upper-right block corresponding to a top-right corner of the current block,
a lower-left block corresponding to a bottom-left corner of the current block, and
an upper-left block corresponding to a top-left corner of the current block,
wherein the upper-right block and the lower-left block have higher priorities than the upper-left block.

US Pat. No. 9,615,091

MOTION PICTURE ENCODING/DECODING APPARATUS, AND METHOD AND APPARATUS FOR HYBRID BLOCK MOTION COMPENSATION/OVERLAPPED BLOCK MOTION COMPENSATION FOR SAME

SK TELECOM CO., LTD., Se...

1. A hybrid block motion compensation/adaptive overlapped block motion compensation (BMC/OBMC) apparatus comprising:
a BMC/OBMC selector configured to perform a pixel-by-pixel selection of one of a block motion compensation (BMC) and an overlapped
block motion compensation (OBMC) with respect to each pixel of a current block according to a preset criterion;

an adaptive motion compensator configured to perform a motion compensation according to the selected one of the BMC and the
OBMC;

a scan mode setter configured to scan the current block in a plurality of scan modes and establish a scan mode causing a smallest
number of transitions between the BMC and the OBMC with respective to each pixel of the current block in the course of the
scanning with respect to the established scan mode; and

an information recorder configured to record transition information at locations of pixels corresponding to the transitions
between the BMC and the OBMC with respective to the established scan mode.

US Pat. No. 9,554,139

ENCODING/DECODING APPARATUS AND METHOD USING FLEXIBLE DEBLOCKING FILTERING

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a video encoder configured to:
generate a prediction block corresponding to a current block,
generate a residual block by subtracting the prediction block from the current block,
encode the residual block by transforming and quantizing the residual block,
reconstruct the residual block by inversely quantizing and inversely transforming the transformed and quantized residual block,
and

reconstruct the current block by adding the prediction block to the reconstructed residual block; and
a deblocking filter configured to filter a boundary between subblocks within a frame including the reconstructed current block,
wherein a first subblock of the subblocks and a second subblock of the subblocks that engage in the filtering are different
from each other in numbers of filtered pixels, depending on one or more predetermined criterion,

wherein the deblocking filter is configured to perform the filtering by applying different pixel disparity values on the first
subblock or the second subblock according to pixel positions relative to the boundary between the first subblock and the second
subblock,

wherein the deblocking filter is configured to
calculate a first pixel disparity value corresponding to a first position from the boundary using a first offset value, and
calculate a second pixel disparity value corresponding to a second position from the boundary using a second offset value,
and

wherein the first offset value and the second offset value are decided irrelevant to pixel values of the first subblock or
the second subblock.

US Pat. No. 9,521,427

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE IN SPATIAL DOMAIN FOR NOISE COMPONENT

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoder, implemented by a processor, configured to reconstruct coding domain information and an encoded residual block from
a bitstream, wherein the coding domain information indicates whether a residual block has been encoded by a frequency domain
coding or by a spatial domain coding, wherein

the frequency domain coding is a coding mode for encoding the residual block into frequency-domain values, and
the spatial domain coding is a coding mode for encoding the residual block into spatial-domain values;
an inverse quantizer, implemented by a processor, configured to inversely quantize the encoded residual block;
an inverse transformer, implemented by a processor, configured to inversely transform the inversely quantized residual block
from the frequency domain into the spatial domain, based on the coding domain information, wherein

(1) when the coding domain information indicates the frequency domain coding, the inverse transformer configured to
inversely transform the inversely quantized residual block from the frequency domain into the spatial domain,
(2) when the coding domain information indicates the spatial domain coding, the inverse transformer configured to
skip a step of inversely transforming the inversely quantized residual block;
a predictor, implemented by a processor, configured to generate a predicted block corresponding to the residual block; and
an adder, implemented by a processor, configured to reconstruct a current block based on the coding domain information by
(A) adding the predicted block to the inversely transformed residual block when the coding domain information indicates the
frequency domain coding, and

(B) adding the predicted block to the inversely quantized residual block when the coding domain information indicates the
spatial domain coding.

US Pat. No. 9,230,166

APPARATUS AND METHOD FOR DETECTING CAMERA TAMPERING USING EDGE IMAGE

SK TELECOM CO., LTD., Se...

1. An apparatus for detecting a camera tampering, the apparatus comprising:
an image capturing unit configured to capture at least one image;
an input-edge-image generating unit configured to
extract an edge image from an object displayed in the captured image and
generate an input edge image by using the extracted edge image;
a reference-edge-image generating unit configured to generate a reference edge image from the input edge image;
a stolen-edge-image generating unit configured to generate a stolen edge image by subtracting the input edge image from the
reference edge image; and

a tampering determining unit configured to
compare the input edge image with the reference edge image for calculating a first similarity between the input edge image
and the reference edge image,

compare the reference edge image with the stolen edge image for calculating a second similarity between the reference edge
image and the stolen edge image, and

determine whether or not a camera tampering has occurred, based on the first similarity and the second similarity.

US Pat. No. 9,185,677

METHOD DEVICE AND SYSTEM FOR ESTIMATING ACCESS POINTS USING LOG DATA

SK TELECOM CO., LTD., Se...

1. A device for estimating an access point (AP) location, the device comprising:
an AP identification information extractor configured to extract terminal AP identification information from a radio signal
received from a terminal;

an AP identification information identifier configured to
identify AP identification information corresponding to the extracted terminal AP identification information, among information
pre-stored in a database, as first AP identification information, and

identify AP identification information which does not correspond to the information pre-stored in the database, among the
extracted terminal AP identification information, as second AP identification information;

a location determiner configured to determine location information of the terminal based on a latitude/longitude coordinate
value assigned to each of the first AP identification information; and

a location estimator configured to
determine the second AP identification information as new log data, and
recognize the location information as location estimation information of the new log data,
wherein the AP identification information identifier is further configured to
compare the new log data with log data pre-stored through another terminal, and
identify AP identification information which corresponds to the log data pre-stored through said another terminal, among the
second AP identification information, as third AP identification information, and

wherein the location estimator is further configured to
calculate a first weight average coordinate value for all weight values assigned to location information assigned to the third
AP identification information, by multiplying each of the location information assigned to each of the third AP identification
information by the corresponding weight value among the assigned weight values, and

recognize the calculated first weight average coordinate value as precise location estimation information.

US Pat. No. 9,813,710

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING SPLIT LAYER

SK TELECOM CO., LTD., Se...

1. A method performed by a video encoding apparatus for encoding a video in a unit of blocks, the method comprising:
encoding, into a bitstream, a first information indicating a minimum block size and a second information indicating an enlarging
ratio relative to the minimum block size; and

dividing a square current block having a maximum block size into one or more subblocks which are equal to or larger than the
minimum block size by a tree structure, and encoding, into the bitstream, partition information of the current block divided
by the tree structure, wherein the maximum block size is identical to a size enlarged from the minimum block size by the enlarging
ratio,

wherein the encoding of the partition information comprises:
encoding, into the bitstream, a partition flag indicating whether or not each node of the tree structure, starting from a
node of an uppermost layer corresponding to the current block, is divided into four nodes of a lower layer,

wherein the partition flag indicating whether a node, which corresponds to a block having the minimum subblock size, is divided
is not encoded into the bitstream.

US Pat. No. 9,654,798

DEVICE AND METHOD FOR IMAGE ENCODING/DECODING USING PREDICTION DIRECTION CONVERSION AND SELECTIVE ENCODING

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus for decoding a current block comprised of a plurality of subblocks by using an intra prediction,
the apparatus including a microprocessor and comprising:
a prediction mode extractor, implemented by the microprocessor, configured to extract an intra prediction mode of the current
block from a bitstream, without extracting intra prediction modes of respective subblocks in the current block from the bitstream;

an inverse quantization unit, implemented by the microprocessor, configured to inversely quantize transformed and quantized
residual subblocks corresponding to the subblocks of the current block to thereby generate transformed residual subblocks;

an inverse transform unit, implemented by the microprocessor, configured to inversely transform the transformed residual subblocks
to thereby reconstruct residual subblocks; and

a reconstructor, implemented by the microprocessor, configured to sequentially reconstruct the subblocks by
predicting a subblock, to be currently reconstructed among the subblocks, from neighboring pixels in one or more subblocks
which have been previously reconstructed in the current block and

adding the predicted subblock and a residual subblock corresponding thereto,
wherein the reconstructor is configured to predict all of the subblocks using an intra prediction mode equal to the intra
prediction mode of the current block among a plurality of intra prediction modes.

US Pat. No. 9,565,444

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING VARIABLE-SIZE MACROBLOCKS

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using a tree structure, the apparatus comprising:
a decoder configured to
decode, from a bitstream, a partition flag indicating whether each block, starting from a block corresponding to an uppermost
layer of the tree structure, is divided into four blocks of a lower layer, and thereby identify a block which is not further
divided,

decode prediction type information on the identified block from the bitstream, and
reconstruct a transformed residual block from the bitstream;
a predictor configured to predict the identified block by using a prediction mode indicated by the prediction type information;
an inverse transformer configured to generate a residual block by inversely transforming the transformed residual block; and
an adder configured to add the predicted block to the residual block,
wherein, when a block of a first layer in the tree structure is divided into four blocks of a second layer which is a lower
layer of the first layer, the decoder is configured to decode the partition flag for each of the four blocks of the second
layer in a predetermined order,

wherein, when a block among the four blocks of the second layer is further divided into four blocks of a third layer which
is a lower layer of the second layer, the decoder is configured to decode the partition flag for each of the four blocks of
the third layer in the predetermined order, before decoding the partition flag for a next block of the second layer in the
predetermined order, and

wherein the predetermined order is an order of an upper left block, an upper right block, a lower left block and a lower right
block.

US Pat. No. 9,532,045

METHOD AND DEVICE FOR ENCODING/ DECODING IMAGE HAVING REMOVABLE FILTERING MODE

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus comprising:
an intra-predictor configured to
predict pixels of a current block by using pixels of a neighboring block to generate an intra-predicted block of the current
block, the neighboring block being adjacent to the current block, and

selectively perform a filtering on the intra-predicted block based on a correlation among values of pixels of the intra-predicted
block to generate a predicted block of the current block;

a subtractor configured to subtract the predicted block from the current block to generate a residual block;
a transformer and quantizer configured to transform and quantize the residual block to generate a transformed and quantized
residual block; and

an encoder configured to encode the transformed and quantized residual block,
wherein the filtering is not performed when the correlation is smaller than a threshold, and
the threshold is determined based on a quantization parameter.

US Pat. No. 9,516,514

METHOD FOR MEASURING POSITION USING A POSITIONING ACCESS POINT, AND DEVICE, SYSTEM, AND ACCESS POINT FOR SAME

SK TELECOM CO., LTD., Se...

1. A positioning apparatus, comprising:
a database configured to store identification information on each of a telecom access point and a positioning access point,
and location information corresponding to the identification information,

wherein the telecom access point is configured to transfer a terminal WLAN signal between a server and a terminal, and
wherein the positioning access point is configured to transmit positioning information to the terminal and is distinguished
from the telecom access point;

an information receiver configured to receive the terminal WLAN signal from the terminal in communication with at least one
of the telecom access point and the positioning access point, in response to a positioning request from the terminal;

a record determination unit configured to determine whether access point identification information in a parameter of the
received terminal WLAN signal is equal to the stored identification information on the positioning access point; and

a positioning determination unit configured to
assign priority to the access point identification information, based on the determination of the record determination unit,
and

determine a location of the terminal by using location information corresponding to the access point identification information,
based on the assigned priority,

wherein the telecom access point is configured to
search the terminal WLAN signal including the positioning information, which is transmitted from the positioning access point,
and

transfer the searched terminal WLAN signal to an access point management server, and
wherein the access point management server is configured to monitor the positioning access point by using the transferred
terminal WLAN signal.

US Pat. No. 9,503,725

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE FOR PERFORMING INTRAPREDICTION USING PIXEL VALUE FILTERED ACCORDING TO PREDICTION MODE

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a prediction unit configured to:
select an intra prediction mode of a current block among a plurality of intra prediction modes;
determine which one of (i) pixels of one or more neighboring blocks of the current block and (ii) pixels generated by filtering
the pixels of the one or more neighboring blocks is to be used as reference pixels for the selected intra prediction mode;
and

generate a predicted block of the current block, by predicting pixel values of the current block from the reference pixels,
according to the selected intra prediction mode of the current block;

determine whether a difference between the pixels of the one or more neighboring blocks and the pixels generated by filtering
is larger than a threshold;
in response to a determination that the difference is larger than the threshold, generate a reference pixel identification
flag which represents which one of the pixels of one or more neighboring blocks of the current block and the pixels generated
by filtering is to be used as reference pixels;
a subtraction unit configured to generate a residual block by subtracting the predicted block from the current block;
a transform unit configured to transform the residual block;
a quantization unit configured to quantize the transformed residual block to generate the quantized residual block; and
an encoding unit configured to encode the quantized transformed residual block.

US Pat. No. 9,363,532

INTRA PREDICTION METHOD AND APPARATUS, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. An intra prediction apparatus for predicting a current pixel of a current block from neighboring blocks, comprising:
a weighted pixel calculator for calculating a plurality of weighted pixel values by applying weights decided by a position
of the current pixel in the current block to pixels in the neighboring blocks; and

a pixel predictor for deriving a predicted pixel value of the current pixel using the weighted pixel values,
wherein the weighted pixel values comprise a first weighted pixel value and a second weighted pixel value, the first weighted
pixel value is calculated by applying a first weight of the weights to a first pixel in an upper side block, and the second
weighted pixel value is calculated by applying a second weight of the weights to a second pixel in a left side block.

US Pat. No. 9,475,402

SYSTEM AND METHOD FOR MANAGING ELECTRIC VEHICLE

SK TELECOM CO., LTD., Se...

1. An electric vehicle management device, comprising:
a communication unit configured to
receive vehicle state information comprising at least one information selected from the group consisting of operation information
of an electric vehicle, a vehicle identification (ID), current position information and destination information, from a terminal
device, and

transmit a vehicle management message to the terminal device;
a vehicle state information database configured to store a reference value for determining whether or not to create the vehicle
management message according to the vehicle state information;

an electric vehicle information database configured to store the ID, the vehicle state information, the destination information
and the current position information of the electric vehicle;

a vehicle state determination unit configured to determine whether or not to create the vehicle management message by comparing
the vehicle state information received through the communication unit with the reference value of the vehicle state information
stored in the vehicle state information database;

an electric vehicle matching unit configured to match an electric vehicle configured to supply power and an electric vehicle
configured to be supplied with the power according to power information, a current position and a destination of each electric
vehicle; and

a vehicle management message creation unit configured to
create the vehicle management message including a place related to the vehicle state information, position information of
other electric vehicles related to the vehicle state information, or a position of the electric vehicle configured to supply
power and route information for moving to the corresponding electric vehicle, based on the current position information of
the electric vehicle according to a result of the determination of the vehicle state determination unit, and

transmit the vehicle management message to the terminal device,
wherein the vehicle management message includes charging history of the electric vehicle which has supplied the power, and
a reward for the electric vehicle according to the charging history, and

wherein the reward is discounted price when a price is charged for power at a charging station.

US Pat. No. 9,473,773

METHOD AND APPARATUS FOR ENCODING FREQUENCY TRANSFORMED BLOCK USING FREQUENCY MASK TABLE, AND METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoder configured to
extract a position information from a bitstream including the position information, wherein the position information indicates
a position of the last coefficient which has a non-zero value in a scanning order within a transform unit, and

generate a transform block having a block size of the transform unit by deriving, from the bitstream, coefficients preceding
the last coefficient in the scanning order based on the position information;

an inverse quantizer configured to inversely quantize the transform block; and
an invese transformer configured to inversely transform the inversely quantized transform block to generate a residual block;
a predictor configured to predict a current block to be decoded to generate a predicted block; and
an adder configured to reconstruct the current block by adding predicted block to the residual block,
wherein the decoder is configured to generate the transform block by
setting coefficients following the last coefficient indicated by the position information in the scanning order to 0, without
extracting, from the bitstream, a value indicating whether or not a coefficient following the last coefficient in the scanning
order is equal to 0,

extracting, from the bitstream, a value indicating whether or not a coefficient preceding the last coefficient in the scanning
order is equal to 0,

deriving the coefficient preceding the last coefficient in the scanning order from the bitstream, when the extracted value
is a first value, and

setting the coefficient preceding the last coefficient in the scanning order to 0, when the extracted value is a second value.

US Pat. No. 9,462,277

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING VARIABLE SIZED MACROBLOCKS

SK TELECOM CO., LTD., Se...

1. A method performed by an apparatus of decoding a video in the unit of blocks, the method comprising:
decoding information on a block size from a bitstream;
determining a maximum block size to be used for decoding an encoded image, based on the information on the block size; and
reconstructing an image by decoding the encoded image using the determined maximum block size,
wherein the information on the block size includes a first information on a minimum block size and a second information on
a difference between the minimum block size and the maximum block size,

wherein the second information has a value of log2 (MB size/X), where MB size is the maximum block size and X is the minimum block size.

US Pat. No. 9,445,101

VIDEO DECODING METHOD USING SKIP INFORMATION

SK TELECOM CO., LTD., Se...

1. A video decoding method, comprising:
determining a size of a minimum block unit in which information on a quantization parameter is decoded from a bitstream;
determining a current block to be decoded by dividing a block larger than 16×16 into one or more blocks;
decoding, from the bitstream, a skip information indicating whether or not the current block has been encoded by using a skip
mode, wherein the skip mode is a mode where no more other information related to the current block is encoded into the bitstream
except motion information for deriving a motion vector of the current block;

when the skip information indicates that the current block has encoded using the skip mod,
decoding the motion information for deriving the motion vector of the current block from the bitstream, and thereby determining
the motion vector of the current block, and

reconstructing the current block directly from a predicted block predicted using the motion vector of the current block, without
decoding information on residual signals of the current block; and

when the skip information indicates that the current block has not been encoded using the skip mode,
decoding prediction information of the current block from the bitstream,
decoding, from the bitstream, quantized transform coefficients which correspond to the current block, when at least one of
the quantized transform coefficients is not zero,

reconstructing residual signals from the quantized transform coefficients, by inversely quantizing the quantized transform
coefficients using a quantization parameter, and

reconstructing the current block based on the prediction information and the reconstructed residual signals
wherein, when a size of the current block is equal to or greater than the size of the minimum block unit, the quantization
parameter is obtained by decoding, from the bitstream, quantization parameter information applied only to the current block,

when the size of the current block is less than the size of the minimum block unit, the quantization parameter is obtained
by decoding, from the bitstream, quantization parameter information applied to all blocks in the minimum block unit in which
the current block is included.

US Pat. No. 9,392,299

METHOD AND APPARATUS FOR VIDEO ENCODING/DECODING USING IMPROVED MERGE

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
an inter predictor configured to
check for whether predetermined candidate adding conditions are satisfied,
add into a merge candidate set including merge candidates corresponding to neighboring blocks of a current block, a combined
bi-predictive motion parameter, the combined bi-predictive motion parameter generated by combining a list 0 motion parameter of a first available candidate block and a list 1 motion parameter of a second available candidate block, when the predetermined candidate adding conditions are satisfied,
and

predict the current block by using a motion parameter corresponding to a merge candidate selected from the merge candidate
set, to thereby generate a predicted block for the current block, wherein

the merge candidate set corresponds to a maximum number of the merge candidates, the maximum number of the merge candidates
corresponding to information on the number of the merge candidates included in a bistream.

US Pat. No. 9,264,721

VIDEO ENCODING/DECODING APPARATUS, DE-BLOCKING FILTER AND FILTERING METHOD BASED ON INTRA-PREDICTION DIRECTIONS FOR SAME, AND RECORDING MEDIA

SK TELECOM CO., LTD., Se...

1. A deblocking filter based on intra-prediction directions, the deblocking filter comprising:
an intra-block identifier configured to identify whether a current block is an intra block,
an intra-prediction direction identifier configured to perform an identification of an intra-prediction direction of the current
block when the current block is the intra block;

a filtering pixel selection unit configured to select a set of pixels for deblocking-filtering between the current block and
a neighboring block based on the intra-prediction direction of the current block; and

a filtering unit configured to perform the deblocking-filtering of the selected set of pixels based on a direction determined
by the intra-prediction direction of the current block in order to remove blocking artifact between the current block and
the neighboring block,

wherein the selected set of pixels positioned in the intra-prediction direction, for each pixel in the boundary of the current
block and the neighboring block, are updated by performing the deblocking-filtering,

wherein, when the determined direction is a diagonal direction,
the filtering unit is configured to select a deblocking direction among the diagonal direction, a horizontal direction and
a vertical direction to perform the deblocking-filtering of the selected set of pixels, based on a relationship between values
of the selected set of pixels, and

the deblocking direction is set to be the diagonal direction when the relationship satisfies a first condition, and the deblocking
direction is set to be the horizontal direction or the vertical direction when the relationship does not satisfy the first
condition, and

wherein the first condition is satisfied when each of pixel value differences between two adjacent pixels in the selected
set of pixels is less than each preset value corresponding to said each of the pixel value differences, and

the selected set of pixels are positioned in the diagonal direction.

US Pat. No. 9,600,469

METHOD FOR DETECTING GRAMMATICAL ERRORS, ERROR DETECTION DEVICE FOR SAME AND COMPUTER-READABLE RECORDING MEDIUM HAVING METHOD RECORDED THEREON

SK TELECOM CO., LTD., Se...

1. A non-transitory computer-readable recording medium storing a program for executing a method for detecting grammatical
errors, the program, when executed by a processor included in an apparatus for detecting grammatical errors, causing the processor
to execute:
breaking up an input sentence into units of morphemes;
generating morpheme sequences by binding the broken-up morphemes in a preset window size set by the processor, the generated
morpheme sequences comprising forward morpheme sequences and backward morpheme sequences;

determining frequencies of appearance of morpheme sequences identical to forward morpheme sequences and backward morpheme
sequences of the generated morpheme sequences by searching an example-based index database (DB); and

detecting grammatical errors in the input sentence by combining the determined frequencies of appearance.

US Pat. No. 9,445,118

APPARATUS AND METHOD FOR MOTION VECTOR ENCODING/DECODING, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using an inter-prediction, the apparatus comprising:
a decoder configured to reconstruct a flag and quantized transform coefficients by decoding a bitstream, the flag indicating
one among a plurality of modes for determining the motion vector of the current block;

a predictor configured to determine a motion vector of a current block to be decoded in a current picture, and predict pixels
in current block using the motion vector of the current block;

an inverse quantizer and inverse transformer configured to inversely quantize and then inversely transform the quantized transform
coefficients to thereby reconstruct residual signals; and

an adder configured to add the predicted pixels to the reconstructed residual signals which correspond to the predicted pixels,
wherein, when the flag indicates a first mode among the plurality of modes, the predictor is configured to
derive a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block, the
plurality of neighboring blocks including one or more of blocks located at left, upper, upper right and upper left sides of
the current block in the current picture,

select a candidate motion vector from the set of candidate motion vectors,
set a predicted motion vector of the current block to the selected candidate motion vector, and
determine the motion vector of the current block by adding the predicted motion vector of the current block to a differential
vector decoded from the bitstream.

US Pat. No. 9,392,300

METHOD AND APPARATUS FOR ENCODING A MOTION VECTOR, AND METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for decoding a current motion vector of a current block in a current frame from a bitstream by determining
a predicted motion vector corresponding to the current motion vector of the current block, the apparatus comprising:
a differential motion vector decoder configured to reconstruct a differential motion vector by decoding an encoded differential
motion vector included in the bitstream;

a motion vector reconstructor configured to:
select one or more motion vector prediction candidates to determine the predicted motion vector corresponding to the current
motion vector,

determine the predicted motion vector among the one or more motion vector prediction candidates, and
reconstruct the current motion vector of the current block by adding the predicted motion vector to the differential motion
vector, and

a prediction candidate identification flag decoder configured to reconstruct a prediction candidate identification flag by
decoding an encoded prediction candidate identification flag,

wherein the motion vector reconstructor is configured to determine a motion vector prediction candidate identified by the
prediction candidate identification flag among the one or more motion vector prediction candidates to be the predicted motion
vector, and

wherein the motion vector reconstructor comprises:
means for selecting one or more of first motion vector prediction candidates from one or more adjacent blocks of the current
block in the current frame, and

means for selecting a second motion vector prediction candidate from a block in a reference frame other than the current frame,
wherein a position of the block in the reference frame is derived based on a position of the current block in the current
frame.

US Pat. No. 9,154,806

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGES USING ADAPTIVE MOTION VECTOR RESOLUTION

SK TELECOM CO., LTD., Se...

1. An apparatus for determining a motion vector of a current block in a current picture, the apparatus comprising:
a resolution determiner configured to determine a motion vector resolution to be applied to the current block or an image
area in which the current block is located; and

a motion vector determiner configured to
identify whether the motion vector of the current block is derived from one or more motion vectors of one or more neighboring
blocks,

when it is identified that the motion vector of the current block is derived from the one or more motion vectors of the one
or more neighboring blocks, determine a first motion vector from the one or more motion vectors of the one or more neighboring
blocks,

convert a motion vector resolution of the first motion vector such that the converted motion vector resolution of the first
motion vector is equal to the motion vector resolution determined by the resolution determiner, when the motion vector resolution
of the first motion vector is different from the motion vector resolution determined by the resolution determiner, and

set the resolution-converted motion vector as the motion vector of the current block.

US Pat. No. 9,706,204

IMAGE ENCODING/DECODING DEVICE AND METHOD

SK TELECOM CO., LTD., Se...

1. A video encoding method, comprising:
determining a size of a minimum block unit among block units in which quantization parameter information is encoded;
determining a current block to be encoded by dividing a block larger than 16×16, wherein the current block is a unit in which
a prediction mode is designated among a skip mode, an inter-prediction mode and an intra-prediction mode;

encoding, into a bitstream, skip mode information indicating whether or not the current block is encoded using the skip mode,
wherein the skip mode is a mode where no more other information related to the current block is encoded into the bitstream
except motion information for deriving a motion vector of the current block after the skip mode information is encoded;

when the current block is encoded using the skip mode,
encoding, into the bitstream, the motion information for deriving the motion vector of the current block without encoding
information on residual signals of the current block; and

when the current block is not encoded using the skip mode,
encoding, into the bitstream, inter or intra prediction information of the current block,
generating residual signals which are differences between pixels in the current block and predicted pixels thereof,
generating quantized transform coefficients of the residual signals, by transforming the residual signals and then quantizing
the transformed residual signals using a quantization parameter, and

encoding the quantized transform coefficients into the bitstream,
wherein, when a size of the current block is equal to or greater than the size of the minimum block unit, information on the
quantization parameter is encoded, into the bitstream, as information dedicated to the current block,

when the size of the current block is less than the size of the minimum block unit, information on the quantization parameter
is encoded, into the bitstream, as information applicable to not only the current block but also other blocks in the minimum
block unit in which the current block is included.

US Pat. No. 9,674,546

METHOD AND APPARATUS FOR INTERPOLATING REFERENCE PICTURE AND METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a video by using an interpolation of a reference picture, comprising:
a resolution determiner configured to determine a motion vector resolution to be applied to a current block to be encoded
or an image area in which the current block is located, the motion vector resolution being determined from among a plurality
of motion vector resolution candidates;

a resolution encoder configured to encode identification information for identifying the determined motion vector resolution;
a reference picture interpolator configured to
select, from among a plurality of interpolation filter candidates, an interpolation filter assigned to the determined motion
vector resolution, and

interpolate pixels of the reference picture by using the selected interpolation filter; and
an inter prediction encoder configured to
predict the current block by using the interpolated pixels of the reference picture to generate a predicted block of the current
block,

generate a residual block by subtracting the predicted block from the current block, and
encode the residual block,
wherein the plurality of interpolation filter candidates includes groups of interpolation filter candidates, the groups of
interpolation filter candidates are assigned respectively to the plurality of motion vector resolution candidates, the groups
of interpolation filter candidates are distinctive from each other, and

wherein the reference picture interpolator is configured to
determine a group of interpolation filter candidates corresponding to the determined motion vector resolution, from among
the groups of interpolation filter candidates, wherein each interpolation filter candidate belonging to the group of interpolation
filter candidates has predefined filter coefficients for sub-pixel positions corresponding to the determined motion vector
resolution,

select, as the interpolation filter, one interpolation filter candidate from interpolation filter candidates belonging to
the determined group of interpolation filter candidates,

generate the interpolated pixels of the reference picture by using predefined filter coefficients of the selected interpolation
filter, and

encode information identifying which interpolation filter candidate is selected as the interpolation filter among interpolation
filter candidates belonging to the determined group of interpolation filter candidates.

US Pat. No. 9,613,060

LOCATION-BASED SERVICE METHOD AND SYSTEM USING LOCATION DATA INCLUDED IN IMAGE DATA

SK TELECOM CO., LTD., Se...

1. A location-based service method using image data provided by a terminal equipped with a camera, and using location data
that includes location information of the terminal, comprising:
generating first image data with the terminal at a predetermined location;
receiving location data of the predetermined location;
prompting a user to choose whether or not to insert the received location data into the first image data to generate a second
image data and, when the user chooses to do so, inserting the received location data into the first image data to generate
a second image data;

transmitting the second image data, the second image data including the first image data and the location data, to another
terminal;

receiving, at the another terminal, a selection input for an image corresponding to the second image data, from the user;
displaying, at the another terminal, an image corresponding to the first image data, and a menu inquiring about whether to
select a location-based service;

receiving, at the another terminal, via the displayed menu, a selection input for the location-based service, from the user;
receiving, at the another terminal, location-based service data corresponding to the location data of the selected second
image data; and

providing the location-based service to the another terminal by using the received location-based service data.

US Pat. No. 9,596,464

METHOD AND DEVICE FOR ENCODING AND DECODING BY USING PARALLEL INTRAPREDICTION BY A CODING UNIT

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a left extrapolation pixel generating unit configured to
select a pixel of a top left block of a coding unit to be encoded, the selection being based on a direction corresponding
to an intra-prediction mode of the coding unit, the top left block being located at an upper left position from the coding
unit, and

generate one or more left extrapolation pixels to be used for an intra prediction of a target pixel within the coding unit,
the target pixel being a pixel to be encoded, the generation being performed by using the pixel of the to left block;

an intra-prediction encoding unit configured to predict, according to the intra-prediction mode, the coding unit by using
neighboring pixels including the left extrapolation pixels to generate a first prediction block to thereby encode the coding
unit, the neighboring pixels being adjacent to the coding unit; and

a prediction information encoding unit configured to encode prediction information including the intra-prediction mode,
wherein the left extrapolation pixels are located in a column nearest from leftmost pixels of the coding unit and located
between the pixel of the top left block and the target pixel,

wherein the pixel of the top left block is located vertically different from the left extrapolation pixels,
wherein the left extrapolation pixels are located in an extension line which connects, in the direction, the pixel of the
top left block and the target pixel.

US Pat. No. 9,571,830

METHOD AND DEVICE FOR ENCODING/DECODING IMAGE BY INTER PREDICTION USING RANDOM BLOCK

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a block partitioning unit configured to determine a partition form, among candidate partition forms, for partitioning a current
block into one or more partition blocks, wherein the candidate partition forms include one or more asymmetric partition forms
in which the current block is partitioned into a plurality of asymmetric partition blocks;

a prediction unit configured to generate one or more predicted blocks respectively corresponding to the one or more partition
blocks;

a subtractor configured to generate a residual block of the current block by subtracting the predicted blocks from one or
more partition blocks corresponding thereto;

a transformer configured to generate at least one transform block by transforming the residual block;
a quantizer configured to generate at least one quantized transform block by quantizing the at least one transform block;
and

an encoder configured to encode the at least one quantized transform block and information on the determined partition form
into a bitstream,

wherein the prediction unit is configured to
determine a scale factor, and
predict a partition block partitioned from the current block, by deriving predicted pixels from a reference picture in a scale
corresponding to the scale factor from a pixel location indicated by a motion vector of the partition block, and

wherein the encoder is configured to encode information on the scale factor into the bitstream to enable a video decoding
apparatus to derive the predicted pixels from the reference picture in a scale corresponding to the information on the scale
factor.

US Pat. No. 9,538,178

DEVICE AND METHOD FOR COMPETITION-BASED INTRA PREDICTION ENCODING/DECODING USING MULTIPLE PREDICTION FILTERS

SK TELECOM CO., LTD., Se...

1. An intra prediction encoding apparatus comprising:
an optimal filter selecting unit configured to
select an intra prediction mode of a current block from among a plurality of intra prediction modes, and
select a filter from among a plurality of filter candidates, wherein the plurality of filter candidates is provided for the
selected intra prediction mode for filtering pixels adjacent to the current block;

a filter updating unit configured to
generate, according to the intra prediction mode of the current block, weight values of pixel values of the pixels adjacent
to the current block with respect to one or more pixel values of the current block, and

generate the plurality of filter candidates, based on the weight values;
a residual signal generating unit configured to
perform a filtering of the pixels adjacent to the current block by using the selected filter,
generate a prediction value of the current block according to the selected intra prediction mode by using the filtered pixels,
and

generate a residual signal by calculating a difference between a generated prediction value of the current block and a pixel
value of the current block;

a transform and quantization unit configured to perform transform and quantization on the residual signal; and
an entropy encoding unit configured to perform an entropy encoding on a transformed and quantized residual signal.

US Pat. No. 9,497,454

METHOD AND DEVICE FOR ENCODING/DECODING IMAGE USING FEATURE VECTORS OF SURROUNDING BLOCKS

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
an intra prediction encoder configured to determine an intra mode of a current block from among a plurality of intra modes,
and

perform an intra prediction and encoding on the current block based on the intra mode of the current block by using pixels
of at least one neighboring block adjacent to the current block;

a feature vector extractor configured to generate a feature vector from pixels of the at least one neighboring block, wherein
the feature vector is generated from a plurality of differences between values of adjacent pixels of the at least one neighboring
block, respective differences of the plurality of differences are calculated based on values of the adjacent pixels located
in respective directions of a plurality of directions, the feature vector includes a plurality of elements, and respective
elements of the plurality of elements correspond to respective differences of the plurality of differences; and

a prediction mode encoder configured to extract, from a preset feature vector distribution, a prediction mode identified by
the feature vector, the preset feature vector distribution including respective feature vectors for respective intra modes,
and

encode the identified prediction mode as a most probable mode (MPM) for the intra mode of the current block,
wherein the MPM is used for predicting the intra mode of the current block, and a length of encoded data for indicating the
intra mode of the current block is determined according to whether the intra mode of the current block is equal to the MPM.

US Pat. No. 9,319,710

VIDEO ENCODING AND DECODING APPARATUS AND METHOD

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a video, the apparatus comprising:
a predictor configured to predict a pixel value of each pixel in a current block of the video to generate a predicted pixel
value;

a subtractor configured to calculate a difference between an original pixel value of said each pixel in the current block
and the predicted pixel value of said each pixel in the current block to generate a residual signal;

a transformer configured to transform the residual signal into frequency coefficients;
a quantizer configured to quantize the transformed frequency coefficients; and
an encoder configured to
scan the quantized frequency coefficients, and
encode the scanned quantized frequency coefficients,
wherein the encoder is configured to use a variable length coding table selected from a plurality of variable length coding
tables for encoding a value of a run_before, the run_before representing the number of zero-level frequency coefficients interposed
between a current non-zero frequency coefficient and a preceding non-zero frequency coefficient,

wherein the variable length coding table is selected from the plurality of variable length coding tables based on a non_zero_left
which represents the number of preceding non-zero frequency coefficients remaining at current non-zero frequency positions
in a direction to a DC coefficient of the scanned quantized frequency coefficients, and

wherein, in each of the plurality of variable length coding tables, a plurality of code words is specified for a combination
of a plurality of values of run_befores and a plurality of values of zero_lefts wherein the encoder is further configured
to encode the scanned quantized frequency coefficients by a context adaptive variable length coding wherein an encoding of
a TotalCoeff, a level and a total zero is included in the encoding of the scanned quantized frequency coefficients, the TotalCoeff
representing the number of non-zero frequency coefficients, the level representing a coefficient value of non-zero frequency
coefficients, the total zero representing the number of frequency coefficients of zeros occurring before a last non-zero frequency
coefficient; wherein the encoder is further configured to encode the scanned quantized frequency coefficients after a zig-zag
scanning, in the order of the level, the totalzero, and the runbefore; wherein the encoder is further configured to encode
a trailingOnes and a trailing ones sign flag, if there exist coefficients having consecutive absolute value of 1 among the
scanned quantized frequency coefficients at the end, the trailingOnes representing the number of coefficients having consecutive
absolute value of 1 at the end, the trailing-onestsignflag representing the sign of the trailingOnes, and wherein the trailingOnes
and the trailing-onestsign-flag are located between the TotalCoeff and the level.

US Pat. No. 9,215,567

LOCAL AREA BROADCASTING SERVICE SYSTEM AND METHOD, AND WIRELESS TRANSMISSION DEVICE APPLIED THEREIN

SK TELECOM CO., LTD., Se...

1. A system having a protocol stack structure for providing a local area broadcast service, the system comprising:
a broadcast server configured to
form contents based on a broadcast transmission protocol and a broadcast transmission conversion protocol, and
transmit the formed contents via a wired network through a transmission protocol of the wired network; and
a wireless transmission apparatus configured to
convert the transmitted contents, which have been received via the wired network through the transmission protocol of the
wired network, to a digital broadcast signal, and

broadcast the digital broadcast signal to a corresponding local area via local area wireless communication through the broadcast
transmission conversion protocol,

wherein, when the transmitted contents correspond to multimedia data, the wireless transmission apparatus is configured to
generate a pilot channel and a broadcast channel corresponding to the transmitted contents,
multiplex the pilot channel and the broadcast channel to obtain a multiplexed signal,
perform a Forward Error Correction (FEC) of the multiplexed signal, and
provide the multiplexed signal after said FEC is performed as the digital broadcast signal, and
wherein, when the transmitted contents do not correspond to multimedia data, the wireless transmission apparatus is configured
to perform the FEC of the transmitted contents and provide the contents after said FEC is performed as the digital broadcast
signal.

US Pat. No. 9,215,463

IMAGE ENCODING/DECODING METHOD AND DEVICE

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
an encoding information encoder configured to
encode a skip information indicating whether a block to be encoded is a skip block, and
encode either a skip motion information of the block, or an intra or inter prediction information of the block and a transform
information of the block, according to whether the block to be encoded is the skip block, wherein the transform information
includes partition information related to partitioning the block into subblocks by a tree structure; and

a video encoder configured to encode a residual signal information of each of the subblocks partitioned from the block,
wherein the encoding information encoder is further configured to encode the partition information by performing a process
comprising:

encoding a side information containing a first information on a difference between a maximum subblock size and a minimum subblock
size and a second information on the minimum subblock size, and

encoding a flag indicating whether each node from a highest layer toward the lowest layer is partitioned into nodes of a lower
layer,

wherein the video encoder encodes the residual signal information of a subblock corresponding to a node which is not further
partitioned.

US Pat. No. 9,143,787

METHOD AND APPARATUS FOR DETERMINING INTRA PREDICTION MODE, AND METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING SAME

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus for determining an intra prediction mode of a current block and selectively encoding information
on the intra prediction mode of the current block, the apparatus comprising:
an intra predictor configured to predict the current block, the intra predictor comprising:
a variation calculator configured to calculate a variation of adjacent pixels in one or more adjacent blocks, wherein the
adjacent pixels are adjacent to the current block and located outside of the current block,

a comparator configured to compare the variation of the adjacent pixels in the adjacent blocks and a threshold, and
a prediction mode determination unit configured to determine the intra prediction mode of the current block, wherein
a predetermined intra prediction mode is determined as the intra prediction mode of the current block when the variation of
the adjacent pixels in the adjacent blocks is below the threshold, and

a particular intra prediction mode from a plurality of intra prediction modes is determined as the intra prediction mode of
the current block when the variation of the adjacent pixels in the adjacent blocks is greater than the threshold; and

an encoder configured
to generate a bitstream by encoding a difference between the predicted current block and the current block,
to encode the information on the determined intra prediction mode of the current block into the bitstream when the variation
of the adjacent pixels in the adjacent blocks is greater than the threshold, and

not to encode the information on the determined intra prediction mode of the current block into the bitstream when the variation
of the adjacent pixels in the adjacent blocks is below the threshold,

wherein the intra prediction mode of the current block indicates a prediction direction of the current block.

US Pat. No. 9,137,532

METHOD AND AN APPARATUS FOR INTER PREDICTION DECODING WITH SELECTIVE USE OF INVERSE QUANTIZATION AND INVERSE TRANSFORM

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using an inter prediction, the apparatus comprising
an information extractor configured to obtain motion information and residual data from encoded data;
a predictor configured to generate a predicted block by performing the inter prediction based on the obtained motion information;
a decoder configured to
identify one or more conditions for enabling an inverse quantization and an inverse transform,
skip both of the inverse quantization and the inverse transform for the obtained residual data to thereby reconstruct a residual
block directly from the obtained residual data, when the one or more identified conditions indicate skipping of both the inverse
quantization and the inverse transform,

inversely quantize the obtained residual data and skip the inverse transform for the inversely quantized residual data to
thereby reconstruct a residual block using the inverse-quantized residual data, when the one or more identified conditions
indicate skipping of the inverse transform, and

inversely quantize the obtained residual data and inversely transform the inversely quantized residual data to thereby reconstruct
a residual block using the inverse transformed residual data, when the one or more identified conditions indicate non-skipping
of both the inverse quantization and the inverse transform; and

an adder configured to add each pixel value of the predicted block to a corresponding pixel value of the reconstructed residual
block.

US Pat. No. 9,137,545

IMAGE ENCODING AND DECODING APPARATUS AND METHOD

SK TELECOM CO., LTD., Se...

1. A method performed by an apparatus for decoding a video in the unit of blocks, the method comprising:
decoding information on a picture size of the video and information on available block sizes from a bitstream;
setting an initial size of a current block to be decoded to the largest block size determined by the information on the available
block sizes;

determining a location of the current block within a picture;
identifying whether the current block is fully located inside the picture, based on the picture size, the size of the current
block and the location of the current block;

when the current block is not fully located inside the picture, resetting the size of the current block to a smaller size
among the available block sizes; and

decoding the current block in the reset size.

US Pat. No. 9,692,846

SYSTEM, DEVICE AND METHOD FOR PROVIDING PUSH SERVICE USING FEEDBACK MESSAGE

SK TELECOM CO., LTD., Se...

1. A system for providing a push service using a feedback message, the system comprising:
a service providing device comprising one or more processors or application specific integrated circuits (ASICs) configured
to transmit a push message to a client device and receive the feedback message with respect to the push message; and

a push service device comprising one or more processors or application specific integrated circuits (ASICs) configured to
receive the push message from the service providing device and transmit the push message to the client device,
receive from the client device a push response message with respect to the push message,
identify whether a transmission of the push message to the client device failed or not through the push response message,
and/or whether a connection of the push service device with the service providing device is disconnected,

generate the feedback message with respect to the failure of the push message and/or the connection identified to be disconnected,
wherein the feedback message includes information indicating that transmitting the push message to the client device has failed,
and based on the feedback message the service providing device stops sending the push message to the client device via the
push service device to reduce network load,

store the generated feedback message when the push message transmitted to the client device is identified to be failed, and/or
when the connection of the push service device with the service providing device is identified to be disconnected, and

transmit the stored feedback message to the service providing device when the push service device identifies a reconnection
with the service providing device, or when the push service device receives a request for the feedback message from the service
providing device.

US Pat. No. 9,648,340

METHOD AND DEVICE FOR ENCODING/DECODING MOTION VECTOR

SK TELECOM CO., LTD., Se...

1. A method performed by a motion vector encoding apparatus for encoding a motion vector of a current block in a unidirectional
complex prediction mode or a bidirectional prediction mode where a plurality of motion vectors are used, the method comprising:
determining a first motion vector resolution for an image area in which the current block is located;
determining a first motion vector of the current block, the first motion vector having the first motion vector resolution
predetermined for the image area;

determining a second motion vector of the current block, the second motion vector having a second motion vector resolution
for the current block, the second motion vector resolution being variably selected among a plurality of motion vector resolutions;

generating a predicted block of the current block by using both (i) the first motion vector in the first motion vector resolution
predetermined for the image area and (ii) the second motion vector in the second motion vector resolution variably selected
for the current block;

determining a predicted motion vector of the first motion vector and a predicted motion vector of the second motion vector;
calculating a first differential motion vector and a second differential motion vector, wherein the first differential motion
vector corresponds to a difference between the first motion vector and the predicted motion vector of the first motion vector,
and the second differential motion vector corresponds to a difference between the second motion vector and the predicted motion
vector of the second motion vector;

encoding the first differential motion vector and the second differential motion vector; and
encoding a motion vector resolution flag for identifying, from the plurality of motion vector resolutions, the second motion
vector resolution for the current block.

US Pat. No. 9,609,334

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING VARIABLE-SIZE MACROBLOCKS

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus using a tree structure, the apparatus comprising:
a splitter configured to generate a partition flag indicating whether each block, starting from a block corresponding to an
uppermost layer of the tree structure, is divided into four blocks of a lower layer; and

an encoder configured to encode, into a bitstream, the partition flag and prediction type information on a block which is
not further divided in the tree structure,

wherein, when a block of a first layer in the tree structure is divided into four blocks of a second layer which is a lower
layer of the first layer, the encoder is configured to encode the partition flag for each of the four blocks of the second
layer in a predetermined order, the predetermined order being an order of an upper left block, an upper right block, a lower
left block and a lower right block,

wherein, when a block among the four blocks of the second layer is further divided into four blocks of a third layer which
is a lower layer of the second layer, the encoder is configured to encode the partition flag for each of the four blocks of
the third layer in the predetermined order, before encoding the partition flag for a next block of the second layer in the
predetermined order.

US Pat. No. 9,596,485

MOTION PICTURE ENCODING/DECODING APPARATUS, ADAPTIVE DEBLOCKING FILTERING APPARATUS AND FILTERING METHOD FOR SAME, AND RECORDING MEDIUM

SK TELECOM CO., LTD., Se...

1. A deblocking filtering apparatus comprising a microprocessor configured to:
determine a boundary among four boundaries corresponding to four sides of a current block, the determined boundary being located
between the current block and a neighboring block adjacent to the current block;

determine a plurality of corresponding filtering directions for boundary pixels along and in the determined boundary of the
current block by selecting, per each boundary pixel of the boundary pixels, each of the plurality of corresponding filtering
directions from among a plurality of candidate directions based on each pixel value difference between relating pixels positioned,
with respect to said each boundary pixel, in every direction of the plurality of candidate directions;

determine a filtering direction for the boundary of the current block, by selecting the determined filtering direction mostly
selected from among the plurality of the determined corresponding filtering directions for said each boundary pixel of the
boundary pixels, wherein each of the plurality of the determined corresponding filtering directions corresponds to said each
corresponding filtering direction for said each boundary pixel of the boundary pixels;

select pixels for filtering based on the determined filtering direction with respect to said each boundary pixel of the boundary
pixels;

determine whether to perform the filtering for the determined filtering direction depending on a first condition on a relationship
between pixel values of the selected pixels for filtering, with respect to said each boundary pixel of the boundary pixels;
and

perform the filtering with respect to the selected pixels for filtering in the determined filtering direction, depending on
the determination of whether to perform the filtering, the filtering being performed, for all the boundary pixels, in the
same determined filtering direction,

wherein said each pixel value difference is calculated corresponding to said each boundary pixel of the boundary pixels.

US Pat. No. 9,497,461

METHOD AND APPARATUS FOR ENCODING FREQUENCY TRANSFORMED BLOCK USING FREQUENCY MASK TABLE, AND METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding method performed by a video decoding apparatus, the method comprising:
generating a predicted block by predicting a current block to be decoded;
extracting a position information from a bitstream including the position information, wherein the position information indicates
a position of the last coefficient which has a non-zero value in a scanning order within a transform unit;

generating a transform block having a block size of the transform unit by deriving, from the bitstream, coefficients preceding
the last coefficient in the scanning order based on the position information;

generating a residual block by inversely quantizing and then inversely transforming the transform block; and
reconstructing the current block by adding the predicted block to the residual block,
wherein the generation of the transform block comprises:
setting coefficients following the last coefficient in the scanning order to 0, without extracting, from the bitstream, a
value indicating whether or not a coefficient following the last coefficient in the scanning order is equal to 0;

extracting, from the bitstream, a value indicating whether or not a coefficient preceding the last coefficient in the scanning
order is equal to 0;

when the extracted value is a first value, reconstructing the preceding coefficient corresponding to the extracted value from
the bitstream; and

when the extracted value is a second value, setting the preceding coefficient corresponding to the extracted value to 0.

US Pat. No. 9,386,099

LOCAL CACHING DEVICE, SYSTEM AND METHOD FOR PROVIDING CONTENT CACHING SERVICE

SK TELECOM CO., LTD., Se...

1. A local caching device, comprising:
a storage unit configured to store some or all content provided by at least one content providing device to at least one user
equipment;

a communication interface configured to transmit and receive data between the at least one content providing device and the
at least one user equipment; and

a controller configured to
receive a content request message transmitted from the at least one user equipment, the content request message includes content
address information,

check whether content corresponding to the content address information is stored in the storage unit,
request the at least one content providing device to transmit the content requested by the at least one user equipment when
the requested content corresponding to the content address information is not stored in the storage unit,

receive from the at least one content providing device a part of the requested content, and
check whether content corresponding to at least one portion of the received part of the requested content is stored in the
storage unit,

wherein the controller is further configured to generate and store a content address management table,
wherein the content address management table includes
a first field in which content identification information generated using at least a part of content stored in the storage
unit is recorded, and

a second field in which one or more addresses of content corresponding to the content identification information are recorded,
and

wherein the content identification information includes all of
prefix information having a predetermined length,
a hash value obtained by processing the prefix information using a predetermined hash function, and
metadata of the received content.

US Pat. No. 9,338,738

SYSTEM, DEVICE AND METHOD FOR PROVIDING SIMULTANEOUS DATA TRANSMISSION SERVICE BASED ON HETEROGENEOUS NETWORKS

SK TELECOM CO., LTD., Se...

1. A transmission device, comprising:
a controller configured to divide data into two or more partial data;
a first communication unit configured to transmit first partial data corresponding to a part of the divided two or more partial
data over a first network; and

a second communication unit configured to transmit second partial data corresponding to another part of the divided two or
more partial data over a second network, the first and second networks being different networks of a heterogeneous network,

wherein the controller is configured to
select the first partial data from the divided two or more partial data according to a first transmission rate for data transmission
to a first network device via the first communication unit,

select the second partial data from the divided two or more partial data according to a second transmission rate for data
transmission to a second network device via the second communication unit,

determine whether at least one of the first transmission rate and the second transmission rate is changed, and
when one or more of the first transmission rate and the second transmission rate are changed as a result of the determination,
(i) select the first partial data from the divided two or more partial data according to the changed first transmission rate,
or

(ii) select the second partial data from the divided two or more partial data according to the changed second transmission
rate, or

(iii) select the first partial data from the divided two or more partial data according to the changed first transmission
rate and select the second partial data from the divided two or more partial data according to the changed second transmission
rate.

US Pat. No. 9,307,255

APPARATUS AND METHOD FOR ENCODING/DECODING MULTI-PLANE IMAGES USING BI-PREDICTION AND RECORDING MEDIUM USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a multi-plane video including two or more color planes by using a bi-prediction, the apparatus
comprising:
an intra-predictor configured to generate a first predicted block of a current block of a current plane by performing an intra-prediction
on the current block based on one or more neighboring blocks of the current block;

an inter-plane predictor configured to generate two or more a second predicted blocks of the current block by performing an
inter-plane prediction based on two or more corresponding blocks of two or more reconstructed previous planes corresponding
to the current block, wherein a position of each of the two or more corresponding blocks in the two or more reconstructed
previous planes corresponds to a position of the current block in the current plane;

a dual-plane predictor configured to generate a third predicted block of the current block based on the first predicted block
and the two or more second predicted blocks;

an optimum mode determiner configured to select a predicted block of the current block from among the first predicted block,
the two or more second predicted blocks, and the third predicted block; and

an encoder configured to encode the current block based on the selected predicted block,
wherein the dual-plane predictor is configured to generate the third predicted block by
giving a weight to the first predicted block and each of weights to each of the two or more second predicted blocks, and
adding the weighted first predicted block and each of the two or more weighted second predicted blocks.

US Pat. No. 9,124,901

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGES CONSIDERING LOW FREQUENCY COMPONENTS

SK TELECOM CO., LTD., Se...

1. A video encoding method performed by a video encoding apparatus, the method comprising:
generating a predicted block by predicting a current block;
generating a residual block by subtracting the predicted block from the current block;
generating quantized transform coefficients by transforming and quantizing the residual block;
generating the encoded image data by encoding the quantized transform coefficients;
reconstructing the residual block by inversely quantizing and inversely transforming the quantized transform coefficients;
generating a reconstructed block by adding the reconstructed residual block to the predicted block;
generating an error block by subtracting the reconstructed block from the current block;
generating encoded low frequency data by encoding one or more low frequency components of the error block, and
reconstructing the current block by adding the reconstructed block and a reconstructed error block generated from the error
block.

US Pat. No. 9,094,690

INTER-PREDICTION METHOD AND VIDEO ENCODING/DECODING METHOD USING THE INTER-PREDICTION METHOD

SK TELECOM CO., LTD., Se...

1. A video encoding method using inter-prediction, comprising:
encoding a first picture, wherein the first picture serves as a random access picture and is encoded without referring to
a reference picture which has already encoded and then decoded;

inter-prediction encoding a block included in a second picture, which is encoded after the first picture and displayed before
the first picture, by using a plurality of reference pictures;

generating reference picture information representing whether one or more past pictures, which are encoded before the first
picture and displayed before the first picture, are used as reference pictures for encoding the second picture; and

transmitting the encoded first and second pictures and the reference picture information,
wherein, when the one or more past pictures are used as the reference pictures for encoding the second picture, the one or
more past pictures are deleted from a memory after encoding at least the second picture.

US Pat. No. 9,544,584

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING BIDIRECTIONAL INTRA PREDICTION

SK TELECOM CO., LTD., Se...

1. An apparatus for encoding a video by using an intra prediction mode of a current block, the apparatus comprising:
an offset calculator configured to
select at least one first neighboring pixel of one or more first neighboring blocks adjacent to the current block, the at
least one first neighboring pixel being located in an extension line of a distal line of the current block, the distal line
of the current block being either a lowermost pixel line of the current block or a rightmost pixel line of the current block,

select at least one second neighboring pixel of one or more second neighboring blocks adjacent to the current block, the at
least one second neighboring pixel being located in an extension line of a neighboring pixel line of the current block, an
inter-pixel direction from the at least one first neighboring pixel to the at least one second neighboring pixel being a direction
of the intra prediction mode of the current block,

wherein the neighboring pixel line is parallel and closest to an uppermost pixel line of the current block when the distal
line is the lowermost pixel line of the current block, and the neighboring pixel line is parallel and closest to a leftmost
pixel line of the current block when the distal line is the rightmost pixel line of the current block, and

calculate an offset between the at least one first neighboring pixel and the at least one second neighboring pixel; and
a prediction unit configured to adaptively perform an intra prediction on the current block based on the calculated offset
so as to generate a predicted block of the current block,

wherein the intra prediction mode of the current block is selected from a plurality of intra prediction modes.

US Pat. No. 9,344,732

IMAGE ENCODING AND DECODING APPARATUS AND METHOD

SK TELECOM CO., LTD., Se...

1. An method of encoding a video in the unit of blocks, the method comprising:
encoding information on a picture size of the video and information on available block sizes;
setting an initial size of a current block to be encoded to a largest block size among the available block sizes;
determining a location of the current block within a picture;
identifying whether the current block is fully located inside the picture, based on the picture size, the size of the current
block and the location of the current block;

resetting the size of the current block to a smaller size among the available block sizes, when the current block is not fully
located inside the picture; and

encoding the current block in the reset size.

US Pat. No. 9,137,546

METHOD AND APPARATUS FOR ENCODING/DECODING MOTION VECTORS OF MULTIPLE REFERENCE PICTURES, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING THE SAME

SK TELECOM CO., LTD., Se...

1. A video decoding method for predicting a current block using an inter prediction, the method comprising:
obtaining, from encoded data, mode information indicating which motion vector encoding mode among a plurality of motion vector
encoding modes is used for determining at least one motion vector of the current block; and

when the obtained mode information indicates a first motion vector encoding mode among the plurality of motion vector encoding
modes, performing a process comprising:

decoding the encoded data to produce a first differential motion vector, a first reference picture index, a second differential
motion vector and a second reference picture index;

deriving, by using motion vectors of one or more neighboring blocks of the current block, a first set of candidate motion
vectors referring to a first reference picture list and a second set of candidate motion vectors referring to a second reference
picture list;

selecting a first candidate motion vector from the first set of candidate motion vectors and a second candidate motion vector
from the second set of candidate motion vectors;

generating a first motion vector of the current block by adding the first candidate motion vector to the first differential
motion vector, and a second motion vector of the current block by adding the second candidate motion vector to the second
differential motion vector; and

generating a predicted block of the current block by using the first motion vector, a first reference picture indicated by
the first reference picture index in first reference picture list, the second motion vector, and a second reference picture
indicated by the second reference picture index in the second reference picture list,

wherein the one or more neighboring blocks are selected from at least one spatially neighboring block of the current block
and at least one temporally neighboring block of the current block, and

wherein, when the at least one temporally neighboring block is selected, the at least one temporally neighboring block is
located within a reference picture included either in the first reference picture list or in the second reference picture
list, and a position of the at least one temporally neighboring block within the reference picture is obtained based on a
position of the current block within a current picture including the current block.

US Pat. No. 9,781,445

METHOD AND APPARATUS FOR ENCODING A MOTION VECTOR, AND METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for reconstructing a current motion vector of a current block in a current frame by determining a predicted
motion vector of the current motion vector, the apparatus comprising:
a differential motion vector decoder configured to reconstruct a differential motion vector by decoding an encoded differential
motion vector included in a bitstream; and

a motion vector reconstructor configured to
derive one or more motion vector prediction candidates to determine the predicted motion vector of the current motion vector,
set the predicted motion vector to a motion vector prediction candidate determined among the one or more motion vector prediction
candidates, and

reconstruct the current motion vector of the current block by adding the predicted motion vector to the differential motion
vector,

wherein the motion vector reconstructor comprises:
means for deriving one or more first motion vector prediction candidates from motion vectors of one or more adjacent blocks
of the current block in the current frame, and

means for deriving a second motion vector prediction candidate from a motion vector of a block in a reference frame decoded
before the current frame, the block in the reference frame being at a same position with the current block or neighboring
to the same position with the current block

wherein the motion vector reconstructor is configured to select one of the first motion vector prediction candidates from
upper blocks adjacent to the current block, and one of the first motion vector prediction candidates from left blocks adjacent
to the current block,

wherein a prediction candidate identification flag decoder configured to reconstruct a prediction candidate identification
flag by decoding an encoded prediction candidate identification flag,

wherein the motion vector reconstructor is configured to set the predicted motion vector to a motion vector prediction candidate
identified by the prediction candidate identification flag among the one or more motion vector prediction candidates.

US Pat. No. 9,729,872

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGES TO MINIMIZE REDUNDANCY OF INTRA-PREDICTION MODE

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
an intra-prediction encoder configured to encode a current block by intra-predicting the current block by using pixels of
neighboring blocks adjacent to the current block; and

a prediction mode encoder configured to encode intra-prediction mode information of the current block, wherein, when among
the neighboring blocks adjacent to the current block there is an absent neighboring block which is not available for an intra-prediction
mode, the prediction mode encoder is configured to encode the intra-prediction mode information of the current block using
a minimum size of bits required for identifying the intra-prediction mode of the current block among a candidate mode group
which includes only available intra-prediction modes.

US Pat. No. 9,686,549

METHOD AND APPARATUS FOR GENERATING A REFERENCE FRAME AND METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING THE SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus for decoding an image, the apparatus comprising:
an offset extractor configured to extract an offset to be applied to a reference frame from encoded data;
an interpolation unit configured to interpolate pixels in the reference frame based on a motion vector of a current block;
an offset adder configured to add the extracted offset to the interpolated pixels to thereby generate a predicted block; and
a decoder configured to
reconstruct residual signals from the encoded data,
reconstruct a residual block by identifying an encoding scheme of the residual signals which is used by a video encoding apparatus
and decoding the residual signals based on the identified encoding scheme, and

reconstruct the current block by adding the reconstructed residual block to the predicted block,
wherein the decoder is configured to reconstruct the residual block,
by skipping both inverse quantization and inverse transform for the residual signals, which have been encoded without performing
both transform and quantization, to thereby reconstruct the residual block having the residual signals for which neither inverse
quantization nor inverse transform is performed, when the identified encoding scheme of the residual signals indicates that
the video encoding apparatus has encoded the residual signals without performing both transform and quantization,

the decoder is configured to reconstruct the residual block by inversely quantizing the residual signals, which have been
encoded by performing quantization without transform, and skipping inverse transform for the inversely quantized residual
signals to thereby reconstruct the residual block having the inversely quantized residual signals for which inverse transform
is not performed, when the identified encoding scheme indicates that the video encoding apparatus has encoded the residual
signals by performing quantization without transform, and

the decoder is configured to reconstruct the residual block by inversely quantizing and then inversely transforming the residual
signals, which have been encoded by performing both transform and quantization, to thereby reconstruct the residual block
having the inversely quantized and inversely transformed residual signals, when the identified encoding scheme indicates that
the video encoding apparatus has encoded the residual signals by performing both transform and quantization.

US Pat. No. 9,628,815

METHOD AND APPARATUS FOR ENCODING/DECODING THE MOTION VECTORS OF A PLURALITY OF REFERENCE PICTURES, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding method using an inter prediction, the method performed by a video decoding apparatus including a microprocessor
and comprising:
reconstructing a first differential motion vector and a second differential motion vector of a current block by decoding encoded
data;

deriving a first predicted motion vector and a second predicted motion vector of the current block from one or more neighboring
blocks of the current block;

generating a first motion vector of the current block by adding the first candidate motion vector to the first differential
motion vector, and a second motion vector of the current block by adding the second candidate motion vector to the second
differential motion vector;

generating a predicted block of the current block by using the first and second motion vectors;
reconstructing a residual block by decoding residual signals included in the encoded data; and
adding each pixel value of the predicted block to a corresponding pixel value of the residual block,
wherein the reconstruction of the residual block comprises:
identifying one or more conditions for enabling an inverse quantization and an inverse transform;
skipping both of the inverse quantization and the inverse transform for the decoded residual signals to thereby reconstruct
the residual block from the decoded residual signals, when the identified one or more conditions indicate skipping of both
the inverse quantization and the inverse transform;

inversely quantizing the decoded residual signals and skipping the inverse transform for the inversely quantized residual
signals to thereby reconstruct the residual block from the inversely quantized residual signals, when the identified one or
more conditions indicate skipping of the inverse transform; and

inversely quantizing the decoded residual signals and inversely transforming the inversely quantized residual signals to thereby
reconstruct the residual block from the inversely quantized and inversely transformed residual signals, when the identified
one or more conditions indicate non-skipping of both the inverse quantization and the inverse transform.

US Pat. No. 9,565,443

METHOD AND APPARATUS FOR CODING/DECODING THROUGH HIGH-SPEED CODING UNIT MODE DECISION

SK TELECOM CO., LTD., Se...

1. An apparatus comprising an encoder and for encoding a current block by sequentially applying a plurality of prediction
unit types to the current block in a predetermined order, the apparatus comprising:
a predictor configured to select one of the prediction unit types in the predetermined order, wherein each of the prediction
unit types indicates a partition type in which the current block is partitioned into one or more prediction units,

generate one or more predicted blocks of a current block by partitioning the current block according to the selected prediction
unit type;

a subtracting unit configured to generate a residual block by the subtracting the predicted blocks from the current block;
a transformer configured to generate a frequency transform block by transforming the residual block;
a quantizer configured to generate a quantized frequency transform block by quantizing the frequency transform block; and
wherein, when the quantized frequency transform block generated by the selected prediction unit type has all zero coefficients,
the predictor is configured to terminate applying, to the current block, remaining prediction unit types subsequent to the
selected prediction unit type in the predetermined order, and to determine the selected prediction unit type as a prediction
unit type for the current block, and

the encoder is configured to encode, into the bitstream, information indicating that the quantized frequency transform block
generated by the selected prediction unit type has all zero coefficients.

US Pat. No. 9,641,844

METHOD AND APPARATUS FOR SELECTING A PREDICTION MODE, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus for predicting a current block in a current frame by using an intra prediction in which the
current block is predicted from one or more of first pixels in one or more of neighboring blocks located in the same current
frame, comprising:
a prediction mode selector configured to select an intra prediction mode of the current block depending on a pixel value variation
of second pixels in the neighboring blocks, the second pixels in the neighboring blocks being located in the same current
frame and adjacent to the current block, wherein the intra prediction mode indicates a prediction direction selected from
a plurality of intra prediction directions to generate a predicted block of the current block when the intra prediction on
the current block is performed, and wherein the second pixels to derive the pixel value variation thereof are selected in
the neighboring blocks irrespective of the intra prediction mode of the current block, whereas the first pixels are selected
in the neighboring blocks according to the intra prediction mode of the current block;

an intra prediction encoder configured to encode a residual block, the residual block being generated by performing the intra
prediction on the current block from the pixels in the neighboring blocks located in the same current frame according to the
selected intra prediction mode of the current block; and

a bitstream generator configured to generate a bitstream including (i) coded coefficient information of the residual block
and (ii) prediction mode information, the prediction mode information representing the selected intra prediction mode of the
current block by the unit of the current block or subblocks thereof, the prediction mode information being selectively encoded
in the bitstream depending on the pixel value variation of the second pixels in the neighboring blocks,

wherein, a preset intra prediction mode is selected as the intra prediction mode of the current block and the prediction mode
information is not encoded into the bitstream, when the pixel value variation is smaller than a threshold, and

the prediction mode information is encoded into the bitstream, when the pixel value variation is greater than the threshold.

US Pat. No. 9,588,737

RANDOM NUMBER GENERATING METHOD AND APPARATUS USING LIGHT SOURCE AND SINGLE PHOTON DETECTOR

SK TELECOM CO., LTD., Se...

1. A random number generating apparatus, comprising:
a light source configured to emit a luminous flux having light intensity distribution symmetrical about a center axis;
a plurality of single-photon detectors (SPDs) arranged at an equal radial distance from an extension line of the center axis
of the light source and configured to generate a plurality of bit strings, each bit string of the plurality of bit strings
having values of either 0 or 1 according to whether corresponding SPD detects a photon or not at each clock period; and

a random number generator configured to generate a random number based on the plurality of bit strings generated from the
plurality of SPDs,

wherein the random number generator is configured to
sequence a plurality of combinations from the plurality of bit strings, each combination including a plurality of bits generated
from the plurality of SPDs at each clock period, and

generate a random number string by performing a parity generating calculation on the each combination.

US Pat. No. 9,584,810

ENCODING/DECODING METHOD AND DEVICE FOR HIGH-RESOLUTION MOVING IMAGES

SK TELECOM CO., LTD., Se...

1. A video encoding method, comprising:
determining a size of a current block to be encoded and encoding information for indicating the size of the current block;
encoding division information related to dividing the current block into one or more subblocks;
encoding the subblocks divided from the current block and reconstructing the subblocks based on transform coefficients, by:
predicting a subblock of the subblocks by using an intra prediction mode corresponding to the subblock,
generating a residual block by subtracting the predicted block from the subblock,
transforming the residual subblock by using a transform size identical to a size of the subblock,
encoding information on transform coefficients in the transformed residual subblock,
inversely transforming the transformed residual subblock by using the transform size identical to the size of the subblock,
and thereby reconstructing the residual subblock, and

reconstructing the subblock by adding the predicted subblock to the reconstructed residual subblock;
deblocking-filtering boundaries between the subblocks in a reconstructed picture including the reconstructed subblocks;
detecting an edge in the deblocking-filtered picture by using at least three pixels which are consecutively arranged; and
adjusting a pixel value of at least one among the at least three pixels, when the edge is detected,
wherein the encoding of the information on the transform coefficients comprises:
selecting a scanning pattern of the subblock among a plurality of scanning patterns, based on a block size of the subblock
and the intra prediction mode of the subblock; and

scanning the transform coefficients of the subblock according to the selected scanning pattern.

US Pat. No. 9,578,330

APPARATUS AND METHOD FOR GENERATING/RECOVERING MOTION INFORMATION BASED ON PREDICTIVE MOTION VECTOR INDEX ENCODING, AND APPARATUS AND METHOD FOR IMAGE ENCODING/DECODING USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoder configured to decode a bitstream received from a video encoding apparatus to
extract a quantization frequency coefficient string from the bitstream to generate a quantized transformed residual block
having the extracted quantization frequency coefficients,

extract motion information including predictive motion vector index and reference frame index, and
extract a differential motion vector from the bitstream;
an inverse-quantization and inverse-transform unit configured to inversely quantize the quantized transformed residual block
into a transformed residual block and inversely transforms the transformed residual block to generate a residual block;

an inter prediction unit configured to
derive a candidate predictive motion vector set by using motion vectors of adjacent blocks of a current block to be decoded,
select a predictive motion vector of the current block from among candidate predictive motion vectors in the candidate predictive
motion vector set, based on the predictive motion vector index,

reconstruct a motion vector of the current block by adding the predictive motion vector and the differential motion vector,
and

reconstruct a prediction block of the current block based on the reconstructed motion vector of the current block and the
reference frame index; and

an adder configured to reconstruct the current block by adding the reconstructed prediction block and the residual block generated
by the inverse-quantization and inverse- transform unit,

wherein the inter prediction unit is configured to
derive a first candidate predictive motion vector based on adjacent blocks located at left side of the current block, and
derive a second candidate predictive motion vector based on adjacent blocks located at upper side of the current block,
wherein the inter prediction unit is configured to select, as the first candidate predictive motion vector, the first valid
motion vector found by sequentially scanning the adjacent blocks in an upward direction, wherein the adjacent blocks are located
at the left side of the current block, and the adjacent blocks include at least one pixel adjacent to the current block.

US Pat. No. 9,571,852

METHOD AND APPARATUS FOR VIDEO ENCODING/DECODING USING IMPROVED MERGE

SK TELECOM CO., LTD., Se...

1. A video encoding method for performing an inter prediction in a merge mode, comprising:
after neighboring candidate blocks of a current block is added into a merge candidate set of merge candidates, checking for
whether predetermined merge candidate adding conditions are satisfied;

adding, into the merge candidate set of merge candidates, one or more combined bi-predictive motion parameters, the combined
bi-predictive motion parameters generated by combining a list 0 motion parameter of a first available candidate block and
a list 1 motion parameter of a second available candidate block, when the predetermined merge candidate adding conditions
are satisfied; and

encoding a merge index into a bitstream for indicating a merge candidate from the merge candidate set, the indicated merge
candidate corresponding to a motion parameter of a predicted block for the current block, wherein

the bitstream includes information on the number of the merge candidates for indicating number of the merge candidates, wherein
the neighboring candidate blocks are added into the merge candidate set, based on a priority order of a left block A>an upper
block B>an upper-right block C>a left-lower block D>an upper-left block E, wherein

the first available candidate block and the second available candidate block used to generate the combined bi-predictive motion
parameters are selected based on a predetermined combination priority, wherein

in the predetermined combination priority, a combination of a first merge candidate having a highest priority in the merge
candidate set and a second merge candidate having a second highest priority in the merge candidate set has a higher priority
than a combination of other merge candidates in the merge candidate set.

US Pat. No. 9,538,173

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE BY USING ADAPTIVE LOOP FILTER ON FREQUENCY DOMAIN USING CONVERSION

SK TELECOM CO., LTD., Se...

1. A video encoding method using a loop filter, the method comprising:
generating a reconstructed image from encoded data of an original image;
determining, in the reconstructed image, one or more regions on which the loop filter is applied;
transforming the original image and the reconstructed image which correspond to each region of the determined one or more
regions from a spatial domain into a frequency domain;

determining loop filter coefficients for said each region by comparing the transformed original image and the transformed
reconstructed image;

loop-filtering the reconstructed image based on the loop filter coefficients for said each region; and
encoding information on the loop filter coefficients for said each region,
wherein the loop-filtering of the reconstructed image comprises:
loop-filtering the transformed reconstructed image in the frequency domain, by using the loop filter coefficients for said
each region; and

inversely transforming the transformed reconstructed image loop-filtered in the frequency domain.

US Pat. No. 9,535,661

METHOD AND DEVICE FOR REMOVING BIASING DUE TO SIGNAL SOURCE DURING RANDOM NUMBER GENERATION

SK TELECOM CO., LTD., Se...

1. A method, performed by a random number generation apparatus, for generating a random number having a signal source biasing
removed, the method comprising:
generating a raw bit string by sampling, at a predetermined cycle, a physical signal input from a signal source; and
generating the random number by performing sequential partial sum on the generated raw bit string,
wherein the sequential partial sum indicates each partial sum calculated by shifting a selection range of sample values by
one bit when a predetermined number of partial sums are selected from among the generated raw bit string.

US Pat. No. 9,473,790

INTER-PREDICTION METHOD AND VIDEO ENCODING/DECODING METHOD USING THE INTER-PREDICTION METHOD

SK TELECOM CO., LTD., Se...

1. A video decoding method using inter-prediction, comprising:
identifying, based on information included in a bitstream, whether a first picture is a picture which allows a second picture
preceding the first picture in a display order to refer to at least one reference picture decoded before the first picture,
wherein the first picture serves as a random access picture;

decoding the first picture without referring to a reference picture which has already decoded;
when the first picture is a picture which allows the second picture to refer to the at least one reference picture decoded
before the first picture,

analyzing reference picture information included in the bitstream, the reference picture information representing reference
pictures used for decoding the second picture among reference pictures including one or more reference pictures decoded before
the first picture, and

inter-prediction decoding, after decoding the first picture, the second picture depending on the reference picture information,
wherein:

the one or more reference pictures decoded before the first picture are adaptively deleted from a memory based on the reference
picture information, and

when the reference picture information represents that the one or more reference pictures decoded before the first picture
are used for decoding the second picture, the one or more reference pictures decoded before the first picture are not deleted
from the memory until the second picture is decoded; and

when the first picture is not a picture which allows the second picture to refer to the at least one reference picture decoded
before the first picture,

inter-prediction decoding, after decoding the first picture, the second picture without using the one or more reference pictures
decoded before the first picture, wherein the one or more reference pictures decoded before the first picture are deleted
from the memory before the first picture is decoded,

wherein,
the memory includes a reference picture list 0 into which past reference pictures displayed before the second picture to be
decoded are inserted and a reference picture list 1 into which future reference pictures displayed after the second picture
to be decoded are inserted, and

the reference picture list 0 is allowed to include, in addition to the past reference pictures, one or more future reference
pictures which are inserted into the reference picture list 1.

US Pat. No. 9,432,364

SYSTEM AND METHOD FOR PROVIDING A SERVICE TO END TERMINAL THAT USES AUTHENTICATION INFORMATION OF ANOTHER MOBILE COMMUNICATION TERMINAL, SERVICE SERVER, MOBILE COMMUNICATION TERMINAL, END TERMINAL, AND STORAGE MEDIUM

SK TELECOM CO., LTD., Se...

1. An end-point terminal for using a service by using authentication information of another mobile communication terminal,
the end-point terminal comprising:
a communication unit for transmitting and receiving data through a short-range communication network;
an input unit for receiving a user command;
a playback unit for playing back service contents received from a service server;
a storage unit for storing authentication information of first and second mobile communication terminals received from the
service server; and

a control unit for controlling operation of each constitutional component and controlling the communication unit to receive
the authentication information of the first mobile communication terminal from the service server in response to the user
command inputted through the input unit, transmit the authentication information of the first mobile communication terminal
to the second mobile communication terminal if the second mobile communication terminal is connected, and transmit an authentication
option inputted through the input unit to the second mobile communication terminal.

US Pat. No. 9,729,881

VIDEO ENCODING/DECODING APPARATUS AND METHOD

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoder, implemented by one or more processors, configured to
determine a size of a minimum block unit among block units in which quantization parameter information is decoded from a bitstream,
determine a current block to be decoded by dividing a block larger than 16×16 into one or more blocks,
decode, from the bitstream, a skip information indicating whether or not the current block has been encoded by using a skip
mode, wherein the skip mode is a mode where no more other information related to the current block is encoded into the bitstream
except motion information for deriving a motion vector of the current block,

decode, from the bitstream, the motion information for deriving the motion vector of the current block without decoding information
on residual signals of the current block, when the skip information indicates that the current block has encoded using the
skip mode, and

decode, from the bitstream, prediction information of the current block and quantized transform coefficients of the current
block, when the skip information indicates that the current block has not been encoded using the skip mode; and

a video reconstructor, implemented by one or more processors, configured to
determine the motion vector of the current block using the decoded motion information and reconstruct, as the current block,
a predicted block predicted using the motion vector of the current block, when the skip information indicates that the current
block has encoded using the skip mode, and

reconstruct residual signals from the quantized transform coefficients by inversely quantizing the quantized transform coefficients
using a quantization parameter and reconstruct the current block based on the prediction information and the reconstructed
residual signals, when the skip information indicates that the current block has not been encoded using the skip mode,

wherein, when a size of the current block is equal to or greater than the size of the minimum block unit, the quantization
parameter is obtained by decoding, from the bitstream, quantization parameter information dedicated to the current block,

when the size of the current block is less than the size of the minimum block unit, the quantization parameter is obtained
by decoding, from the bitstream, quantization parameter information applicable to all blocks in the minimum block unit in
which the current block is included.

US Pat. No. 9,706,222

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING HIGH-PRECISION FILTER

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus, comprising:
a decoding unit, implemented by one or more processors, configured to extract motion information on a current block to be
decoded and a quantized frequency-transformed block from a bitstream;

an inverse quantization unit, implemented by one or more processors, configured to reconstruct a frequency-transformed block
based on inversely quantizing the quantized frequency-transformed block;

an inverse transform unit, implemented by one or more processors, configured to reconstruct a residual block based on inversely
transforming the frequency-transformed block;

a prediction unit, implemented by one or more processors, configured to determine a motion vector of the current block based
on the extracted motion information, and generate a prediction block based on interpolating chroma sub-samples of a reference
block in a reference frame referenced by the motion vector of the current block; and

an addition unit, implemented by one or more processors, configured to reconstruct the current block based on adding the reconstructed
residual block and the prediction block,

wherein the prediction unit is configured to
calculate non-divided values of a first set of sub-samples by multiplying chroma integer-pixels of the reference frame by
integer numerators and summing the multiplied chroma integer-pixels,

derive the first set of sub-samples by dividing the non-divided values by a common denominator, and
derive a second set of sub-samples by interpolation from the non-divided values of the first set of sub-samples, not from
the first set of sub-samples which have been divided by the common denominator, and then division by the common denominator.

US Pat. No. 9,691,141

IMAGE CORRECTION DEVICE FOR ACCELERATING IMAGE CORRECTION AND METHOD FOR SAME

SK TELECOM CO., LTD., Se...

1. A video correction apparatus, comprising:
a resolution adjuster configured to
determine one or more resolution values and a filter coefficient of at least one filter for performing filtering process for
extracting an illumination component from a color component of an input image, and

adjust an initial resolution of the color component of the input image to the one or more resolution values to generate one
or more resolution-adjusted images;

an illumination component extractor configured to extract one or more illumination components from the one or more resolution-adjusted
images by using the one or more resolution-adjusted images the at least one filter;

a reflection component extractor configured to extract one or more reflection components of the one or more resolution-adjusted
images by removing the one or more illumination components from the one or more resolution-adjusted images;

a color adjuster configured to generate one or more sum images by using the one or more reflection components and the one
or more resolution-adjusted images; and

an image synthesizer configured to
generate one or more readjusted images by readjusting the one or more resolutions of the one or more sum images to the initial
resolution of the color component of the input image, and

generate a corrected image corresponding to the color component of the input image by using the one or more readjusted images.

US Pat. No. 9,686,562

METHOD AND DEVICE FOR ENCODING/DECODING IMAGE BY INTER PREDICTION USING RANDOM BLOCK

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a block partitioning unit configured to determine a partition form, among candidate partition forms, for partitioning a current
block into one or more partition blocks, wherein the candidate partition forms include one or more asymmetric partition forms
in which the current block is partitioned into a plurality of asymmetric partition blocks;

a prediction unit configured to generate one or more predicted blocks respectively corresponding to the one or more partition
blocks by

determining a motion vector of a partition block partitioned from the current block, and
predicting the partition block using the motion vector and a scale factor which indicates a ratio of pixel sampling, wherein
the partition block is predicted from samples in a reference picture which are located at pixel positions identified by both
of the motion vector and the scale factor;

a subtractor configured to generate a residual block of the current block by subtracting the predicted blocks from one or
more partition blocks corresponding thereto;

a transformer configured to generate at least one transform block by transforming the residual block;
a quantizer configured to generate at least one quantized transform block by quantizing the at least one transform block;
and

an encoder configured to encode, into the bitstream, information on the scale factor, information on the determined partition
form, information on the motion vector and the at least one quantized transform block.

US Pat. No. 9,648,329

METHOD AND APPARATUS FOR PREDICTIVE ENCODING/DECODING OF MOTION VECTOR

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a predictor configured to generate a predicted block of a current block corresponding to a predicted motion vector and a differential
motion vector; and

an entrophy encoder configured to encode an index for use in identifying the predicted motion vector of the current block
and the differential motion vector in a bitstream,

wherein the predicted motion vector of the current block corresponds to a motion vector identified by the index in an inter
prediction mode, and

wherein the index corresponds to at least one of representative blocks determined using neighboring blocks of the current
block, in consideration of priorities of block positions,

wherein the at least one of representative blocks is determined in consideration of a difference between a first picture order
count (POC) corresponding to a first reference picture of a neighboring block and a second picture order count (POC) corresponding
to a second reference picture of the current block, when a first inter prediction direction corresponding to the neighboring
block and a second inter prediction direction corresponding to the current block are identical.

US Pat. No. 9,602,834

METHOD AND APPARATUS FOR ENCODING/DECODING VIDEO USING HIGH-PRECISION FILTER

SK TELECOM CO., LTD., Se...

1. A video encoding apparatus, comprising:
a prediction unit, implemented by one or more processors, configured to generate a prediction block based on interpolating
chroma sub-samples of a reference frame referenced by a motion vector of a current block;

a subtraction unit, implemented by one or more processors, configured to generate a residual block based on subtracting the
prediction block from the current block;

a transform unit, implemented by one or more processors, configured to generate a frequency-transformed block based on transforming
the residual block;

a quantization unit, implemented by one or more processors, configured to generate a quantized frequency-transformed block
based on quantizing the frequency-transformed block; and

an encoding unit, implemented by one or more processors, configured to encode the quantized frequency-transformed block into
a bitstream,

wherein the prediction unit is configured to
calculate non-divided values of a first set of sub-samples by multiplying chroma integer-pixels of the reference frame by
integer numerators and summing the multiplied chroma integer-pixels,

derive the first set of sub-samples by dividing the non-divided values by a common denominator, and
derive a second set of sub-samples by interpolation from the non-divided values of the first set of sub-samples, not from
the first set of sub-samples which have been divided by the common denominator, and then division by the common denominator.

US Pat. No. 9,542,383

EXAMPLE-BASED ERROR DETECTION SYSTEM FOR AUTOMATIC EVALUATION OF WRITING, METHOD FOR SAME, AND ERROR DETECTION APPARATUS FOR SAME

SK TELECOM CO., LTD., Se...

1. An error detection system for automatically evaluating writing, the system comprising:
an example construction apparatus, implemented by one or more processors and/or application-specific integrated circuits (ASICs),
configured

to collect example sentences including various literary styles,
to break up the collected example sentences in units of morphemes, and
to construct the example sentences in an example-based index database (DB); and
an error detection apparatus, implemented by one or more processors and/or application-specific integrated circuits (ASICs),
configured

to break up an input sentence in units of morphemes,
to generate one or more morpheme sequences by binding one or more morphemes of the broken up input sentence in a forward direction
or a backward direction in an arbitrary window size based on each morpheme to which the part of speech has been tagged, wherein
the one or more morpheme sequences includes (i) forward morpheme sequences generated by binding morphemes positioned in the
forward direction in the arbitrary window size and (ii) backward morpheme sequences by binding morphemes positioned in the
backward direction in the arbitrary window size, and the arbitrary window size is determined based on a size of each morpheme
sequence, and

wherein the one or more morpheme sequences are generated by varying the arbitrary window size,
to search the example-based index DB for each of the one or more morpheme sequences,
to extract a frequency at which each morpheme searched is arranged from the one or more morpheme sequences;
to calculate a frequency for occurring to arrange each morpheme of the broken-up input sentence in a corresponding morpheme
sequence among the one or more morpheme sequences searched for through the example-based index DB, and

to detect an error section based on the calculated frequency, and by determining whether there is a section having a compatibility
score for each morpheme that is lower than a threshold, or decreased by a predetermined value or more,

wherein the error detection apparatus is further configured to calculate the compatibility for each of the forward morpheme
sequences and the backward morpheme sequences generated, and to calculate integrated compatibility reflecting the compatibility.

US Pat. No. 9,521,406

METHOD AND APPARATUS FOR PREDICTIVE ENCODING/DECODING OF MOTION VECTOR

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus for predicting a current block to be decoded, the apparatus comprising:
a bitstream decoder configured to extract an index for use in identifying a predicted motion vector of the current block and
a differential motion vector from a bitstream; and

a predictor configured to generate a predicted block of the current block based on the predicted motion vector and the extracted
differential motion vector,

wherein the predicted motion vector of the current block is determined to be a motion vector identified by the extracted index
in a motion estimation mode of an inter prediction mode, and

wherein the extracted index corresponds to one or more representative blocks determined using neighboring blocks of the current
block, in consideration of priorities of block positions,

wherein the one or more representative blocks are determined in considering of a difference between a first picture order
count (POC) corresponding to a first reference picture of a neighboring block and a second picture order count (POC) corresponding
to a second reference picture of the current block when a first inter prediction direction corresponding to the neighboring
block and a second inter prediction direction corresponding to the current block are identical.

US Pat. No. 9,478,032

IMAGE MONITORING APPARATUS FOR ESTIMATING SIZE OF SINGLETON, AND METHOD THEREFOR

SK TELECOM CO., LTD., Se...

1. An image monitoring apparatus, comprising:
a foreground/background separator configured to generate a foreground image by removing background pixels exhibiting no movement
from pixels in an image and separating foreground pixels representing pixels of a moving object from the pixels in the image;

a foreground object information generator configured to generate foreground object information containing (i) a coordinate
value of each of one or more foreground objects included in the foreground image and (ii) the number of pixels of the foreground
objects;

a clustering unit configured to cluster the foreground object information into a plurality of groups;
a singleton information detector configured to
determine at least one group from the plurality of groups as a group of singletons and
detect singleton information on the singletons; and
a singleton estimation calculator configured to
estimate a predetermined area calculation function using the singleton information and
calculate at least one of estimates with respect to an area, a width and a height of each of the singletons.

US Pat. No. 9,130,908

TRANSMITTING DEVICE, RECEIVING DEVICE, AND OPERATION METHOD THEREOF

SK TELECOM CO., LTD., Se...

1. A transmitting device, comprising:
a data dividing unit configured to
predefine a security condition in which data to be transmitted over a plurality of types of networks are forcedly divided
to reinforce security of the data;

firstly divide the data into two or more partial data,
secondly divide at least one data packet included in the firstly divided two or more partial data into two or more partial
data packets when the firstly divided two or more partial data or a receiving device corresponds to the predefined security
condition,

determine a first network and a second network to transmit the secondly divided two or more partial data packets, and
insert network access information into the secondly divided two or more partial data packets based on the determined first
network and second network;

a data providing unit configured to provide (i) a first partial data packet corresponding to one part of the two or more partial
data packets and (ii) a second partial data packet corresponding to another part of the two or more partial data packets through
a multi-communication unit; and

the multi-communication unit supporting the plurality of types of networks and configured to simultaneously transmit the first
partial data packet and the second partial data packet to the receiving device respectively through the first network and
the second network which are different types of networks established in a single session.

US Pat. No. 9,749,653

MOTION VECTOR ENCODING/DECODING METHOD AND DEVICE AND IMAGE ENCODING/DECODING METHOD AND DEVICE USING SAME

SK TELECOM CO., LTD., Se...

1. An apparatus of encoding a video using an inter prediction, the apparatus comprising:
a motion vector encoder configured to determine a current motion vector of a current block to be encoded;
a motion compensator configured to generate a predicted block by predicting the current block using the current motion vector;
a subtractor configured to generate a residual block by subtracting the predicted block from the current block; and
a residual data encoder configured to
identify whether transform from a spatial domain into a frequency domain and quantization are applied to residual signals
in the residual block, and

encode, into a bitstream, the residual signals in the residual block by selecting, based on the identification of whether
the transform and the quantization are applied, one of the following processes:

transforming and then quantizing the residual signals to thereby encode the transformed and quantized residual signals,
skipping the transform of the residual signals and quantizing the residual signals to thereby encode the quantized residual
signals which are not transformed, and

skipping both the transform and the quantization to thereby encode the residual signals which are neither transformed nor
quantized.

US Pat. No. 9,628,814

MOTION VECTOR ENCODING/DECODING METHOD AND DEVICE AND IMAGE ENCODING/DECODING METHOD AND DEVICE USING SAME

SK TELECOM CO., LTD., Se...

1. A method of decoding a video using inter prediction, the method comprising:
obtaining a differential motion vector of a current block and encoded residual signals from a bitstream;
defining a candidate set including a plurality of predicted motion vector candidates by deriving the plurality of predicted
motion vector candidates from neighboring blocks of the current block;

selecting a predicted motion vector of the current block from the plurality of predicted motion vector candidates included
in the candidate set;

predicting pixels in the current block by using the obtained differential motion vector and the selected predicted motion
vector;

identifying whether an inverse quantization and an inverse transform from a frequency domain into a spatial domain are to
be applied to the encoded residual signals;

reconstructing residual signals from the encoded residual signals by selecting, based on the identification of whether the
inverse quantization and the inverse transform are to be applied to the encoded residual signals, one of the following processes:

skipping both the inverse quantization and the inverse transform from the frequency domain into the spatial domain, to reconstruct
the residual signals directly from the encoded residual signals which are neither inversely quantized nor inversely transformed,

inversely quantizing the encoded residual signals and skipping the inverse transform of the inversely quantized residual signals
from the frequency domain into the spatial domain, to reconstruct the residual signals using the inversely quantized residual
signals which are not inversely transformed, and

inversely quantizing the encoded residual signals, and then inversely transforming the inversely quantized residual signals
from the frequency domain into the spatial domain, to reconstruct the residual signals using the inversely quantized and inversely
transformed residual signals; and

adding the predicted pixels and the reconstructed residual signals corresponding to the predicted pixels,
wherein the neighboring blocks for deriving the plurality of predicted motion vector candidates include:
adjacent blocks which are located in a current frame including the current block, and are adjacent to the current block, and
at least one block which is located in a reference frame other than the current frame, wherein a location of the at least
one block in the reference frame is determined based on a location of the current block in the current frame.

US Pat. No. 9,491,483

INTER-PREDICTION METHOD AND VIDEO ENCODING/DECODING METHOD USING THE INTER-PREDICTION METHOD

SK TELECOM CO., LTD., Se...

1. A video encoding method using inter-prediction, comprising:
encoding information indicating whether a first picture is a picture which allows a second picture preceding the first picture
in a display order to refer to at least one reference picture encoded before the first picture, wherein the first picture
serves as a random access picture;

encoding the first picture without referring to a reference picture which has already encoded;
when the first picture is a picture which allows the second picture to refer to the at least one reference picture encoded
before the first picture,

inter-prediction encoding, after encoding the first picture, the second picture by using a plurality of reference pictures,
and

encoding reference picture information representing the reference pictures used for encoding the second picture among reference
pictures including one or more reference pictures encoded before the first picture, wherein:

the one or more reference pictures encoded before the first picture are adaptively deleted from a memory based on whether
or not the one or more reference pictures encoded before the first picture are used for encoding the second picture, and

when the one or more reference pictures encoded before the first picture are used as the reference pictures for encoding the
second picture, the one or more reference pictures encoded before the first picture are not deleted from the memory until
the second picture is encoded; and

when the first picture is not a picture which allows the second picture to refer to the at least one reference picture encoded
before the first picture,

inter-prediction encoding, after encoding the first picture, the second picture without using the one or more reference pictures
encoded before the first picture, wherein the one or more reference pictures encoded before the first picture are deleted
from the memory before the first picture is encoded,

wherein,
the memory includes a reference picture list 0 into which past reference pictures displayed before the second picture to be encoded are inserted and a reference picture
list 1 into which future reference pictures displayed after the second picture to be encoded are inserted, and

the reference picture list 0 is allowed to include, in addition to the past reference pictures, one or more future reference pictures which are inserted
into the reference picture list 1.

US Pat. No. 9,313,525

INTRA PREDICTION METHOD AND APPARATUS, AND IMAGE ENCODING/DECODING METHOD AND APPARATUS USING SAME

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus using an intra prediction, the apparatus comprising:
a decoder configured to decode a bitstream to thereby extract residual signals;
an inverse quantizer configured to inversely quantize the residual signals;
an inverse transformer configured to inversely transform the inversely quantized residual signals;
an intra predictor configured to predict a current block from a plurality of neighboring blocks of the current block; and
an adder configured to add the inversely transformed residual signals to the predicted pixels in the predicted block,
wherein the intra predictor comprises:
a weighted pixel calculator configured to calculate a plurality of weighted pixel values of pixels selected in the neighboring
blocks by applying weights to the pixels selected in the neighboring blocks, wherein the weights are decided variably based
on a position of a current pixel to be predicted in the current block; and

a pixel predictor configured to derive a predicted pixel value of the current pixel using the weighted pixel values, and
wherein the pixels selected in the neighboring blocks comprise:
a first pixel which is included in an upper neighboring block and located at the same column with the current pixel; and
a second pixel which is included in a left neighboring block and located at the same row with the current pixel.

US Pat. No. 9,674,551

VIDEO ENCODING AND DECODING METHOD USING AN INTRA PREDICTION

SK TELECOM CO., LTD., Se...

1. A method performed by a video encoding or decoding apparatus for intra-predicting a current block in a video image by dividing
the current block into a plurality of subblocks, the method comprising:
determining an intra prediction mode of the current block among a plurality of intra prediction modes, wherein
the determined intra prediction mode of the current block is applied to all of the subblocks in the current block and thereby
intra prediction modes of respective subblocks in the current block are not included in a bitstream, and

each of the subblocks has a plurality of pixels; and
sequentially reconstructing all of the subblocks in the current block by predicting a subblock, to be reconstructed among
the subblocks in the current block, from at least one neighboring subblock which has already reconstructed among the subblocks
in the current block using an intra prediction mode identical to the determined intra prediction mode of the current block,

wherein each subblock in the current block is reconstructed by:
predicting the subblock to be reconstructed in the current block, based on the determined intra prediction mode of the current
block,

generating a residual subblock corresponding to the subblock to be reconstructed, and
generating a reconstructed subblock by adding the predicted subblock to the residual subblock,
wherein the subblock to be reconstructed in the current block is predicted using one or more neighboring pixels which are
selected from pixels of the at least one neighboring subblock already reconstructed in the current block, wherein the one
or more neighboring pixels are selected from the pixels of the at least one neighboring subblock using the intra prediction
mode identical to the determined intra prediction mode of the current block.

US Pat. No. 9,621,895

ENCODING/DECODING METHOD AND DEVICE FOR HIGH-RESOLUTION MOVING IMAGES

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus comprising:
a decoder configured to
decode division information related to dividing a current block into subblocks, each of the subblocks being a unit of transform,
wherein the division information allows the subblocks in the current block to have various sizes, and

reconstruct transform coefficients of each of the subblocks identified by the division information, to thereby generate transformed
residual subblocks;

an inverse transformer configured to inverse-transform each of the transformed residual subblocks, and thereby generate residual
subblocks;

a predictor configured to generate predicted subblocks by intra-predicting each of the subblocks;
an adder configured to reconstruct the current block by adding the predicted subblocks to the residual subblocks corresponding
thereto;

a first filter configured to perform deblocking-filtering on boundaries between the subblocks in a reconstructed picture including
the reconstructed current block; and

a second filter configured to
detect an edge in the deblocking-filtered picture, by using at least three pixels which are consecutively arranged, and
adjust a pixel value of at least one among the at least three pixels when the edge is detected.

US Pat. No. 9,575,955

METHOD OF DETECTING GRAMMATICAL ERROR, ERROR DETECTING APPARATUS FOR THE METHOD, AND COMPUTER-READABLE RECORDING MEDIUM STORING THE METHOD

SK TELECOM CO., LTD., Se...

1. An apparatus for detecting grammatical errors, the apparatus comprising:
a sentence analyzer configured to
break up a sentence into units of morphemes,
tag the morphemes with parts of speech, and
analyze a syntactic structure of the sentence based on the tagged parts of speech;
a first error detector configured to
generate part-of-speech sequences using n-grams of the tagged parts of speech, and
detect first grammatical errors by analyzing the generated part-of-speech sequences based on grammatical rules;
a second error detector configured to
generate morpheme sequences by binding the morphemes in a preset n-window size, wherein n is an integer, and
detect second grammatical errors according to frequencies of appearance of morpheme sequences identical to the generated morpheme
sequences by searching examples from an example-based index database (DB); and

an integrated error detector configured to determine final grammatical errors in the sentence by combining the detected first
grammatical errors and the detected second grammatical errors,

wherein the second error detector comprises a second error detection unit, the second error detection unit is configured to:
search whether or not the morpheme sequences identical to the generated morpheme sequences are in the example-based index
DB;

extract the frequencies of appearance of the morpheme sequences identical to the generated morpheme sequences, and calculating
respective suitability scores of the morpheme sequences based on the extracted frequencies of appearance; and

detect second grammatical errors by determining whether the suitability scores are smaller than a threshold or whether the
suitability scores are changed larger than a predetermined value, and

wherein when the second error unit calculates the suitability scores, the second error detection unit is further configured
to, when the morpheme sequences generated in the second error detecting step include both forward morpheme sequences and backward
morpheme sequences,

extract frequencies at which each morpheme of the morphemes is arranged with the forward morpheme sequences and the backward
morpheme sequences,

calculate suitability scores of each morpheme of the morphemes based on the extracted frequencies, and
calculate an integrated suitability score in consideration of the suitability scores of each morpheme of the morphemes.

US Pat. No. 9,667,705

METHOD OF DATA TRANSMISSION OVER MULTIPLE NETWORKS, AND APPARATUS THEREFOR

SK TELECOM CO., LTD., Se...

1. A receiving apparatus comprising:
a communication unit, implemented by one or more processors, configured to
receive two or more partial data transmitted from a transmitting apparatus, wherein the two or more partial data are partitioned
from data and are simultaneously transmitted through two or more networks including at least first and second networks being
different networks of a heterogeneous network, and the two or more partial data include one or more first partial data transmitted
through the first network and one or more second partial data transmitted through the second network, and

transfer network state related information to the transmitting apparatus, the network state related information including
information on a difference between times of receiving the two or more partial data through the first network and the second
network; and

a network selection unit, implemented by one or more processors, configured to
determine uplink transmission performance based on the times of receiving the two or more partial data respectively transmitted
through the first network and the second network of the two or more network, and

designate the first network for a uplink path among the two or more networks based on the determination of the uplink transmission
performance, the uplink path used for transmitting to the transmitting apparatus the network state related information,

wherein when a request for changing the uplink path is received from the transmitting apparatus, the network selection unit
is configured to change the uplink path to be designated from the first network to the second network.

US Pat. No. 9,609,335

METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE USING VARIABLE-SIZE MACROBLOCKS

SK TELECOM CO., LTD., Se...

1. A video decoding apparatus for reconstructing residual signals of a current block to be decoded by using a tree structure,
the apparatus comprising:
a decoder configured to
decode, from a bitstream, prediction type information on the current block to be decoded, and
divide, by the tree structure, the current block into one or more subblocks of which information on residual signals is to
be reconstructed, by decoding, from the bitstream, a partition flag which indicates whether a block corresponding thereto
is divided into blocks of a lower layer in the tree structure, wherein blocks which are not further divided are identified
as the subblocks of which information on the residual signals is to be reconstructed; and

a reconstructor configured to reconstruct information on the residual signals of each of the subblocks from the bitstream,
wherein, when a block of a first layer in the tree structure is divided into a plurality of blocks of a second layer which
is a lower layer of the first layer, the decoder is configured to decode the partition flag for each of the blocks of the
second layer in a predetermined order, the predetermined order being an order of an upper left block, an upper right block,
a lower left block and a lower right block, and

wherein, when a block among the blocks of the second layer is further divided into a plurality of blocks of a third layer
which is a lower layer of the second layer, the decoder is configured to decode the partition flag for each of the blocks
of the third layer in the predetermined order, before decoding the partition flag for a next block of the second layer in
the predetermined order.

US Pat. No. 9,531,917

DEVICE AND METHOD FOR EXTRACTING CORRELATION PARAMETERS BETWEEN COLOUR PLANES FOR PREDICTION, AND A RECORDING MEDIUM FOR THE SAME

SK TELECOM CO., LTD., Se...

1. An apparatus for predicting a first block of a current plane by using correlation parameters between color planes, the
apparatus comprising:
a neighboring block searching unit configured to
search for a second block in a reconstructed previous plane based on a location of the first block in the current plane, wherein
a position of the second block in the reconstructed previous plane is same as the location of the first block in the current
plane, and

select a third block among neighboring blocks of the second block in the reconstructed previous plane, wherein a pixel value
difference between the second block and the third block is a minimum among respective pixel value differences between the
second block and respective neighboring blocks of the second block;

a correlation parameter calculator configured to
search for a fourth block in the current plane based on a location of the third block in the reconstructed previous plane,
wherein a position of the fourth block in the current plane is same as the location of the third block in the reconstructed
previous plane,

calculate the correlation parameters between the third block and the fourth block; and
a predictor configured to predict the first block based on the second block and the correlation parameters,
wherein the first block includes a plurality of pixels, and
wherein the first block, the second block, the third block and the fourth block are same each other in both size and shape.